Add ability to communicate with elasticsearch using a service token (backport #226)

[mergify]

This is an automatic backport of pull request #226 done by Mergify.

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[elasticmachine]

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Build stats

• Build Cause: Pull request #237 opened

• Start Time: 2021-04-14T14:35:49.942+0000

• Duration: 5 min 16 sec

• Commit: ba0ce69

Test stats 🧪

Test	Results
Failed	0
Passed	69
Skipped	0
Total	69

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