[autobackport: sssd-2-9] tests: Clarify approx match filter

[sssd-bot]

This is an automatic backport of PR#8714 tests: Clarify approx match filter to branch sssd-2-9, created by @justin-stephenson.

Please make sure this backport is correct.

Note

The commits were cherry-picked without conflicts.

You can push changes to this pull request

git remote add sssd-bot git@github.com:sssd-bot/sssd.git
git fetch sssd-bot refs/heads/SSSD-sssd-backport-pr8714-to-sssd-2-9
git checkout SSSD-sssd-backport-pr8714-to-sssd-2-9
git push sssd-bot SSSD-sssd-backport-pr8714-to-sssd-2-9 --force

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Original commits
21674dd - tests: Clarify approx match filter

Backported commits

• 892d2e4 - tests: Clarify approx match filter

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Original Pull Request Body

Debugging this test for an unrelated issue (new failover) lead to several questions about 'approximate match' filter, adding some comments to make it more clear after some investigation.

[gemini-code-assist]

Code Review

This pull request adds explanatory comments to the LDAP access control filter tests to clarify provider-specific behaviors for approximate matching across AD, Samba, and 389ds. It also includes a note on how Samba handles unsupported filters during authentication checks. I have no feedback to provide as there were no review comments to assess.

[thalman]

Correctly backported