fix: rename as_bytes to as_byte in ReadableSize (#428)

[zouxiang1993]

Which issue does this PR close?

Closes #428

Rationale for this change

Refer to #428

What changes are included in this PR?

• Rename the method as_bytes of ReadableSize to as_byte.

Are there any user-facing changes?

None.

How does this change test

Existing tests.

[CLAassistant]

All committers have signed the CLA.

[ShiKaiWi]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

zouxiang1993 seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
You have signed the CLA already but the status is still pending? Let us recheck it.

@zouxiang1993 Would you like to sign the CLA: Contributor License Agreement?

[codecov-commenter]

Codecov Report

Merging #766 (d031e1c) into main (8a9635e) will decrease coverage by 0.02%.
The diff coverage is 60.00%.

❗ Current head d031e1c differs from pull request most recent head 2c1a69f. Consider uploading reports for the commit 2c1a69f to get more accurate results

@@            Coverage Diff             @@
##             main     #766      +/-   ##
==========================================
- Coverage   68.34%   68.32%   -0.02%     
==========================================
  Files         296      296              
  Lines       46315    46315              
==========================================
- Hits        31656    31647       -9     
- Misses      14659    14668       +9     

Impacted Files	Coverage Δ
server/src/server.rs	0.00% <0.00%> (ø)
analytic_engine/src/setup.rs	56.00% <40.00%> (ø)
analytic_engine/src/compaction/picker.rs	84.44% <50.00%> (ø)
analytic_engine/src/compaction/scheduler.rs	74.41% <100.00%> (ø)
analytic_engine/src/instance/open.rs	80.74% <100.00%> (ø)
common_util/src/config.rs	87.02% <100.00%> (ø)

... and 3 files with indirect coverage changes

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[zouxiang1993]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
zouxiang1993 seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
You have signed the CLA already but the status is still pending? Let us recheck it.

@zouxiang1993 Would you like to sign the CLA: Contributor License Agreement?

I have already signed and got a message "You have agreed to the CLA for CeresDB/ceresdb Version: 2022-09-13" in CLA assistant.