extension: fix make enterprise-server failed

[lcwangchao]

What problem does this PR solve?

Issue Number: close #47646

What is changed and how it works?

1. fix make enterprise-server failed
2. detect pkg/extension/enterprise/.git to check whether we can get enterprise git hash because .git/modules/extension/enterprise always exits even folderpkg/extension/enterprise not exist

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[codecov]

Codecov Report

Merging #47658 (2a2da40) into master (34bc3a1) will increase coverage by 0.9105%.
Report is 1 commits behind head on master.
The diff coverage is n/a.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #47658        +/-   ##
================================================
+ Coverage   71.9564%   72.8669%   +0.9105%     
================================================
  Files          1396       1419        +23     
  Lines        404738     411310      +6572     
================================================
+ Hits         291235     299709      +8474     
+ Misses        93906      92775      -1131     
+ Partials      19597      18826       -771     

Flag	Coverage Δ
integration	41.2334% <ø> (?)
unit	71.9709% <ø> (+0.0144%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	53.9913% <ø> (ø)
parser	∅ <ø> (∅)
br	48.7049% <ø> (-4.2487%)	⬇️

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: CbcWestwolf, hawkingrei

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• OWNERS [CbcWestwolf,hawkingrei]

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-10-16 07:49:44.579541213 +0000 UTC m=+1643382.166651357: ☑️ agreed by CbcWestwolf.
• 2023-10-16 07:57:02.929112842 +0000 UTC m=+1643820.516222989: ☑️ agreed by hawkingrei.