webui add remove user to groups not case sensitive

[haribhandari07]

Description

Add webui tests to:

• add users using different case of the username (UID)

• add and delete groups using different case of the group name, checking that distinct groups are being managed

• add and delete users in groups, using different case of user and group name, making sure that distinct groups are managed correctly, and the user names behave in the "opposite" way (they are not case-sensitive)

Related Issue

• Fixes

Motivation and Context

Screenshots (if appropriate):

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Database schema changes (next release will require increase of minor version instead of patch)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Technical debt
• [x] Tests only (no source changes)

Checklist:

• [ ] Code changes
• [ ] Unit tests added
• [x] Acceptance tests added
• [ ] Documentation ticket raised:

Open tasks:

• [ ] Backport (if applicable set "backport-request" label and remove when the backport was done)

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