fix: correct file mime type validation parameter to restore functionality

[guqing]

What type of PR is this?

/kind bug /area core /milestone 2.20.x

What this PR does / why we need it:

修复文件上传时类型校验失效的问题

此问题由 #6390 导致

Does this PR introduce a user-facing change?

修复文件上传时类型校验失效的问题

[f2c-ci-robot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.

Project coverage is 58.08%. Comparing base (6cd8dc8) to head (dc33187). Report is 80 commits behind head on main.

Files with missing lines	Patch %	Lines
...achment/endpoint/LocalAttachmentUploadHandler.java	0.00%	12 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #6673 +/- ## ============================================ - Coverage 58.18% 58.08% -0.10% - Complexity 3774 3925 +151 ============================================ Files 651 674 +23 Lines 22125 23068 +943 Branches 1538 1574 +36 ============================================ + Hits 12873 13400 +527 - Misses 8641 9048 +407 - Partials 611 620 +9 ```

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