ci(clang-tidy-review): Fix for qt6 + swap to docker-ci container

[joshtrichards]

• Fix cmake command line for qt6 (as already has been done for other CI tests)
• Switch to the ci-client-qt6 image for consistency with other tests and to eliminate package install step

Let's see how the CI run likes it in the first pass...

[nextcloud-desktop-bot]

AppImage file: nextcloud-PR-6860-5c3c6a81405df2ab2fc14c2273905734f0d1b8cb-x86_64.AppImage

To test this change/fix you can simply download above AppImage file and test it.

Please make sure to quit your existing Nextcloud app and backup your data.

[sonarqubecloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

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