Make sure functions aren't marked as App Services

[Jeremy Voss (jeremydvoss)]

Description

Functions can have WEBSITE_SITENAME. Make sure prefix does not count functions as app services.

All SDK 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.

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.

[Copilot]

Pull Request Overview

This PR ensures that Azure Functions environments are detected before App Service in the attach logic so Functions sites aren’t misclassified as App Service.

• Reordered conditions in _is_attach_enabled to check for Functions first, then App Service.
• Updated test cases to include WEBSITE_SITE_NAME alongside FUNCTIONS_WORKER_RUNTIME.
• Added a CHANGELOG entry for this bug fix.

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
_utils.py	Swapped order of _is_on_functions() and _is_on_app_service() checks in _is_attach_enabled.
tests/test_utils.py	Added WEBSITE_SITE_NAME to environment patches for Functions tests.
CHANGELOG.md	Documented the fix for not counting Functions as App Service.