CI: Remove unneeded runtime deps

Removes kernel headers and dkms packages from the CI pipeline. These are
only needed when running obs and not when building. This avoids crashing
and burning in CI when secureboot is enabled. see: https://github.com/obsproject/obs-studio/pull/4560/checks?check_run_id=2403303957

.github/workflows/main.yml

@@ -425,9 +425,7 @@ jobs:
            qtbase5-private-dev \
            libqt5svg5-dev \
            swig \
-           libcmocka-dev \
-           linux-generic \
-           v4l2loopback-dkms
+           libcmocka-dev
       - name: 'Restore Chromium Embedded Framework from cache'
         id: cef-cache
         uses: actions/cache@v2.1.2