fix: admin mode UI buttons missing on bigger screen sizes

What does this MR do?

Re-enable admin mode feature buttons on bigger screen sizes, incorrectly disabled on !17529 (merged) (see screenshot below).

Additionally, corrected capitalisation of admin mode UI buttons message.

Fixes #33453 (closed)

The development of this MR is sponsored by Siemens (/cc @bufferoverflow)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
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• Style guides
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• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

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• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team