Add config example for LDAP groupOfUniqueNames group structure

[zmiguel]

Based on #1517

Adding a comment to the LDAP group section of the config file to tell users they need to use a different group_filter if their LDAP groups use the groupOfUniqueNames structure instead of the expected groupOfNames structure.

Not doing so result in Authelia not finding the groups for the user and not authorizing group-based access.

[authelia]

Thanks for choosing to contribute @zmiguel. We lint all PR's with golangci-lint, I may add a review to your PR with some suggestions.

You are free to apply the changes if you're comfortable, alternatively you are welcome to ask a team member for advice.

Artifacts

These changes once approved by a team member will be published for testing on Buildkite and DockerHub.

Docker Container

• docker pull authelia/authelia:PR1549

[james-d-elliott]

LGTM, which LDAP standard/backend are you using? RFC4519?

Also just need to adjust this file too (same change as the config template):

https://github.com/authelia/authelia/blob/master/docs/configuration/authentication/ldap.md

[codecov]

Codecov Report

Merging #1549 (318eedb) into master (d5904bd) will not change coverage.
The diff coverage is n/a.

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  Hits         2653     2653           
  Misses       1133     1133           
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Flag	Coverage Δ
backend	66.68% <ø> (ø)
frontend	64.60% <ø> (ø)

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[zmiguel]

LGTM, which LDAP standard/backend are you using? RFC4519?

I'm using OpenLDAP configured to use RFC2307BIS_SCHEMA

I initialized my LDAP database using the wheelybird/ldap-user-manager docker container that uses groupOfUniqueNames by default for groups.

This pull request is to provide more information to new users that might be using the same setup on their docker deployments that they need to change the group filter so authelia correctly picks up the groups for the given username.

[james-d-elliott]

LGTM

[james-d-elliott]

I was just curious for the future, it's nice to know what our users are using so we can setup LDAP implementation templates like this: https://www.authelia.com/docs/configuration/authentication/ldap.html#implementation

Thanks for contributing! If you were interested in contributing in a future PR we could assist either via GitHub, Matrix, or Discord (see badges on https://github.com/authelia/authelia to join Matrix/Discord).