tidbmonitor add additional volume configuration

[mikechengwei]

What problem does this PR solve?

Add additional volume and volumeMount configuration.

Code changes

• Has Go code change

Tests

• Unit test
• E2E test
• Manual test

Release Notes

TidbMonitor add additional volume and volumeMount configurations.

[codecov-io]

Codecov Report

Merging #3855 (c34fbbe) into master (83a34d5) will increase coverage by 0.87%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #3855      +/-   ##
==========================================
+ Coverage   67.78%   68.65%   +0.87%     
==========================================
  Files         173      173              
  Lines       18449    18455       +6     
==========================================
+ Hits        12505    12670     +165     
+ Misses       4860     4682     -178     
- Partials     1084     1103      +19     

Flag	Coverage Δ
e2e	42.76% <0.00%> (+2.65%)	⬆️
unittest	62.35% <0.00%> (-0.05%)	⬇️

[mikechengwei]

/test pull-e2e-kind

[mikechengwei]

/test pull-e2e-kind-serial

[handlerww]

LGTM

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• handlerww
• july2993

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[mikechengwei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: fe21edf