Enhance the validation of local media_save API

[ninghu]

Description

Please add an informative description that covers that changes made by the pull request and link all relevant issues.

All Promptflow Contribution checklist:

• [ ] The pull request does not introduce [breaking changes].
• [ ] CHANGELOG is updated for new features, bug fixes or other significant changes.
• [ ] I have read the contribution guidelines.
• [ ] I confirm that all new dependencies are compatible with the MIT license.
• [ ] Create an issue and link to the pull request to get dedicated review from promptflow team. Learn more: suggested workflow.

General Guidelines and Best Practices

• [ ] Title of the pull request is clear and informative.
• [ ] There are a small number of commits, each of which have an informative message. This means that previously merged commits do not appear in the history of the PR. For more information on cleaning up the commits in your PR, see this page.

Testing Guidelines

• [ ] Pull request includes test coverage for the included changes.

[github-actions[bot]]

promptflow SDK CLI Azure E2E Test Result users/ninhu/media_save_fix

  4 files    4 suites   4m 18s :stopwatch: 244 tests 204 :white_check_mark:  40 :zzz: 0 :x: 976 runs  816 :white_check_mark: 160 :zzz: 0 :x:

Results for commit e938323b.

[github-actions[bot]]

SDK CLI Global Config Test Result users/ninhu/media_save_fix

6 tests   6 :white_check_mark:  1m 31s :stopwatch: 1 suites  0 :zzz: 1 files    0 :x:

Results for commit e938323b.

[github-actions[bot]]

Executor Unit Test Result users/ninhu/media_save_fix

798 tests   798 :white_check_mark:  3m 44s :stopwatch:   1 suites    0 :zzz:   1 files      0 :x:

Results for commit e938323b.

[github-actions[bot]]

Executor E2E Test Result users/ninhu/media_save_fix

246 tests   239 :white_check_mark:  5m 2s :stopwatch:   1 suites    6 :zzz:   1 files      1 :x:

For more details on these failures, see this check.

Results for commit e938323b.

[github-actions[bot]]

SDK CLI Test Result users/ninhu/media_save_fix

    4 files      4 suites   1h 4m 57s :stopwatch:   790 tests   767 :white_check_mark: 23 :zzz: 0 :x: 3 160 runs  3 068 :white_check_mark: 92 :zzz: 0 :x:

Results for commit e938323b.