Update migration-api-overview.md by adding notice on file-level auditing events

[zuojihong]

Add file-level auditing statement

Category

• Content fix
• New article
• Example checked item (delete this line)

DELETE THIS LINE BEFORE SUBMITTING | For the above list, an empty checkbox is [ ] as in [SPACE]. A checked checkbox is [x] with no space between the brackets. Use the PREVIEW tab at the top right to preview the rendering before submitting your issue.

Related issues

• fixes #issuenumber
• partially #issuenumber
• mentioned in #issuenumber

DELETE THIS LINE BEFORE SUBMITTING | If this fixes (aka: closes) or references an issue, please reference it here. This helps maintaining the issue list as it will (1) link the PR to the issue & (2) automatically close the issue when this PR is merged in.

What's in this Pull Request?

DELETE THIS LINE BEFORE SUBMITTING | Please describe the changes in this PR. Sample description or details around bugs which are being fixed.

Submission guidelines

• !!IMPORTANT!! - All submissions must complete the baseline sections included in this template. Ignoring or deleting this template may result in closing the issue with the label type:incomplete-submission.
• Follow our guidance on How To Create Good Pull Requests.
• Target the main branch of this repo.
• When changing a page, ensure you update the ms.date front matter wih the current date in the format MM/DD/YYYY.
• Review all build checks and address the automated errors, warnings, and suggestions.
• NOTE: The live site is based on the live branch. Site owners periodically refresh live branch from the main branch so merged PRs won't immediately appear on the live site. Please be patient to see your changes appear on the live site.

DELETE THIS SECTION BEFORE SUBMITTING

[learn-build-service-prod]

Learn Build status updates of commit 9532d01:

✅ Validation status: passed

File	Status	Preview URL	Details
docs/apis/migration-api-overview.md	✅Succeeded	View

For more details, please refer to the build report.

For any questions, please:

• Try searching the learn.microsoft.com contributor guides
• Post your question in the Learn support channel

[andrewconnell]

Thank you for the PR, but it is incomplete. You must complete the instructions in the PR template found in your OP to help us better understand what & why this PR is for.

Please refer to the guidance, linked from this repo's README.md, on How to Create a Good Pull Request.

Following the guidance & completing the default template is required for all PRs to be reviewed in this repo.

[andrewconnell]

Bump... @zuojihong this PR can't be reviewed because it's incomplete. Please see my last comment and address this. Thanks

[andrewconnell]

@zuojihong - changing this PR to draft mode... once you've completed the PR submission, you can change it to open to get reviewed.