[Experimental] Enable prev/next for beforeApiDocs items

[sserrata]

Description

Adds prev/next button support for beforeApiDocs items.

Motivation and Context

Improves navigation.

How Has This Been Tested?

Screenshots (if appropriate)

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes if appropriate.
• All new and existing tests passed.

[github-actions]

Size Change: +638 B (0%)

Total Size: 2.52 MB

Filename	Size	Change
demo/build/assets/js/42c07454.********.js	3.83 kB	+132 B (+4%)
demo/build/assets/js/466dcb64.********.js	1.45 kB	+60 B (+4%)
demo/build/assets/js/52d34678.********.js	1.02 kB	+142 B (+16%)	⚠️
demo/build/assets/js/9f85b634.********.js	1.46 kB	+65 B (+5%)	🔍
demo/build/assets/js/a30588cf.********.js	7.86 kB	+64 B (+1%)
demo/build/assets/js/c76c11f6.********.js	998 B	+119 B (+14%)	⚠️
demo/build/assets/js/d38d1999.********.js	8.54 kB	+56 B (+1%)

ℹ️ View Unchanged

Filename	Size
demo/.docusaurus/globalData.json	2.22 kB
demo/build/assets/css/styles.********.css	87.7 kB
demo/build/assets/js/010b0d5d.********.js	1.38 kB
demo/build/assets/js/021c2319.********.js	12.9 kB
demo/build/assets/js/09ead32c.********.js	10.2 kB
demo/build/assets/js/0c270917.********.js	7.59 kB
demo/build/assets/js/0cb18c9d.********.js	11.7 kB
demo/build/assets/js/0e384e19.********.js	2.41 kB
demo/build/assets/js/1181d397.********.js	6.41 kB
demo/build/assets/js/16abef02.********.js	6.6 kB
demo/build/assets/js/17896441.********.js	12.6 kB
demo/build/assets/js/18c41134.********.js	14.7 kB
demo/build/assets/js/1bbda95d.********.js	19.8 kB
demo/build/assets/js/1be78505.********.js	11.1 kB
demo/build/assets/js/1e4232ab.********.js	3.46 kB
demo/build/assets/js/1f391b9e.********.js	2.62 kB
demo/build/assets/js/22648341.********.js	1.28 kB
demo/build/assets/js/2391.********.js	10.1 kB
demo/build/assets/js/25013e4a.********.js	4.76 kB
demo/build/assets/js/26fa5e84.********.js	1.3 kB
demo/build/assets/js/2c32bac3.********.js	1.73 kB
demo/build/assets/js/2d2458d1.********.js	12.9 kB
demo/build/assets/js/2ee8962c.********.js	1.5 kB
demo/build/assets/js/31d12231.********.js	1.61 kB
demo/build/assets/js/341550c5.********.js	5.52 kB
demo/build/assets/js/3620.********.js	1.1 MB
demo/build/assets/js/3914806c.********.js	4.83 kB
demo/build/assets/js/393be207.********.js	926 B
demo/build/assets/js/428b4c57.********.js	9.61 kB
demo/build/assets/js/4c5e977b.********.js	36.1 kB
demo/build/assets/js/4eeb3c5d.********.js	4.46 kB
demo/build/assets/js/51e890c3.********.js	9.55 kB
demo/build/assets/js/52c4b3e2.********.js	6.6 kB
demo/build/assets/js/533a09ca.********.js	2.81 kB
demo/build/assets/js/5388d76b.********.js	13.3 kB
demo/build/assets/js/54843f7d.********.js	5.75 kB
demo/build/assets/js/5aa5a9cd.********.js	2.89 kB
demo/build/assets/js/5c868d36.********.js	3.54 kB
demo/build/assets/js/60b38b8e.********.js	1.42 kB
demo/build/assets/js/60e13cef.********.js	10.2 kB
demo/build/assets/js/6119.********.js	1.02 kB
demo/build/assets/js/6533f3d7.********.js	6.78 kB
demo/build/assets/js/69ba2909.********.js	5.53 kB
demo/build/assets/js/6a7cf16d.********.js	12.3 kB
demo/build/assets/js/6ce157fc.********.js	5.75 kB
demo/build/assets/js/6ed40b15.********.js	1.72 kB
demo/build/assets/js/72390392.********.js	6.4 kB
demo/build/assets/js/79147915.********.js	11.2 kB
demo/build/assets/js/7a5457fa.********.js	7.81 kB
demo/build/assets/js/7cc518f2.********.js	2.81 kB
demo/build/assets/js/822bd8ab.********.js	3.21 kB
demo/build/assets/js/8826c0db.********.js	9.87 kB
demo/build/assets/js/8e36997c.********.js	12.3 kB
demo/build/assets/js/8e44c742.********.js	11.2 kB
demo/build/assets/js/935f2afb.********.js	3.54 kB
demo/build/assets/js/94214df4.********.js	12.6 kB
demo/build/assets/js/98463c12.********.js	4.48 kB
demo/build/assets/js/9a562316.********.js	1.06 kB
demo/build/assets/js/a172e59e.********.js	10.6 kB
demo/build/assets/js/a356afa7.********.js	10.6 kB
demo/build/assets/js/a5c48ae3.********.js	6.77 kB
demo/build/assets/js/a6966617.********.js	10.2 kB
demo/build/assets/js/ac3cc3f5.********.js	10.9 kB
demo/build/assets/js/af70375d.********.js	9.56 kB
demo/build/assets/js/b5257597.********.js	4.17 kB
demo/build/assets/js/b5efbc84.********.js	1.42 kB
demo/build/assets/js/b68d1b59.********.js	9.62 kB
demo/build/assets/js/b9572ad5.********.js	1.66 kB
demo/build/assets/js/ba5ac426.********.js	5.94 kB
demo/build/assets/js/bac076bc.********.js	13.3 kB
demo/build/assets/js/bde5d56a.********.js	9.43 kB
demo/build/assets/js/be3e95ec.********.js	5.57 kB
demo/build/assets/js/c4403e14.********.js	8.56 kB
demo/build/assets/js/c4f5d8e4.********.js	72.3 kB
demo/build/assets/js/c87b34e1.********.js	9.42 kB
demo/build/assets/js/common.********.js	125 kB
demo/build/assets/js/d01652cd.********.js	12.6 kB
demo/build/assets/js/d6cb8c6d.********.js	1.65 kB
demo/build/assets/js/dd1a1797.********.js	9.88 kB
demo/build/assets/js/dd2855f3.********.js	5.95 kB
demo/build/assets/js/dff1c289.********.js	4.21 kB
demo/build/assets/js/e44a2883.********.js	5.47 kB
demo/build/assets/js/e4da18c0.********.js	10.2 kB
demo/build/assets/js/e91d46ba.********.js	1.66 kB
demo/build/assets/js/ee030bdf.********.js	1.55 kB
demo/build/assets/js/f13f1da7.********.js	19.9 kB
demo/build/assets/js/f55d3e7a.********.js	3.03 kB
demo/build/assets/js/f6149237.********.js	5.58 kB
demo/build/assets/js/fd1ce97f.********.js	1.55 kB
demo/build/assets/js/fefa319c.********.js	11.7 kB
demo/build/assets/js/main.********.js	410 kB
demo/build/assets/js/runtime~main.********.js	8.24 kB
demo/build/index.html	72.6 kB

_{compressed-size-action}

[github-actions]

Visit the preview URL for this PR (updated for commit fe59e14):

https://docusaurus-openapi-36b86--pr45-bumc5oz5.web.app

_{(expires Thu, 05 May 2022 21:41:15 GMT)}

_{🔥 via Firebase Hosting GitHub Action 🌎}

[blindaa121]

Looks good! 🚀