Add note about function app limitation on route names starting with admin

[mitiko]

Routes of function apps can't be prefixed with admin, this includes function names, and /api prefixes.

Related issues:

• Functions doesn't allow function name or route /api/admin Azure/azure-functions-host#1781
• Cannot have [FunctionName] starting with 'admin' Azure/azure-functions-host#7634
• https://github.com/MicrosoftDocs/azure-docs/issues/80267

Link to StackOverflow answer.
Link to Admin API docs.

Closes #80267

[prmerger-automator]

@mitiko : Thanks for your contribution! The author(s) have been notified to review your proposed change.

[learn-build-service-prod]

Learn Build status updates of commit 546166f:

💡 Validation status: suggestions

File	Status	Preview URL	Details
articles/azure-functions/functions-bindings-http-webhook-trigger.md	💡Suggestion		Details

articles/azure-functions/functions-bindings-http-webhook-trigger.md

• Line 1, Column 1: [Suggestion: uhf-header-id-missing] uhfHeaderID should not be null; specify the uhfHeaderID in global metadata of docfx.json file.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

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[learn-build-service-prod]

Learn Build status updates of commit 340a605:

💡 Validation status: suggestions

File	Status	Preview URL	Details
articles/azure-functions/functions-bindings-http-webhook-trigger.md	💡Suggestion		Details

articles/azure-functions/functions-bindings-http-webhook-trigger.md

• Line 1, Column 1: [Suggestion: uhf-header-id-missing] uhfHeaderID should not be null; specify the uhfHeaderID in global metadata of docfx.json file.

For more details, please refer to the build report.

Note: Your PR may contain errors or warnings or suggestions unrelated to the files you changed. This happens when external dependencies like GitHub alias, Microsoft alias, cross repo links are updated. Please use these instructions to resolve them.

For any questions, please:

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

[American-Dipper]

@ggailey777 - can you review the proposed changes?

IMPORTANT: When the changes are ready for publication, add a #sign-off comment to signal that the PR is ready for the review team to merge.

#label:"aq-pr-triaged"

@MicrosoftDocs/public-repo-pr-review-team

[denrea]

Sent reminder to ggailey777

[American-Dipper]

email and Teams msg to author

[mitiko]

Hey guys, any update on this one?
@ggailey777, @American-Dipper

[American-Dipper]

This addition was made via another PR.

[mitiko]

@American-Dipper Can you link the PR, I was not able to find it. Does it touch the same file?
Please also close the related issue, thanks!