CI: replace 'prepare' step with a script in the Calamares repo

This applies to the Debian nightly builds; having to go through
external actions doubles the effort to debug these kinds of
scripts, so just slap the actual commands into the workflow.
This also makes it easier to migrate to a different hosting.

.github/workflows/nightly-debian.yml

@@ -22,7 +22,49 @@ jobs:
       options: --tmpfs /build:rw --user 0:0
     steps:
       - name: "prepare env"
-        uses: calamares/actions/prepare-debian@v5
+        shell: bash
+        run: |
+          apt-get update
+          # Make sure we can send notices later
+          apt-get -y install git-core jq curl
+          apt-get -y install \
+            build-essential \
+            cmake \
+            extra-cmake-modules \
+            gettext \
+            libatasmart-dev \
+            libappstreamqt-dev \
+            libboost-python-dev \
+            libicu-dev \
+            libparted-dev \
+            libpolkit-qt5-1-dev \
+            libqt5svg5-dev \
+            libqt5webkit5-dev \
+            libyaml-cpp-dev \
+            os-prober \
+            pkg-config \
+            python3-dev \
+            qtbase5-dev \
+            qtdeclarative5-dev \
+            qttools5-dev \
+            qttools5-dev-tools
+          # Same name as on KDE neon, different version
+          apt-get -y install libkpmcore-dev
+          # Additional dependencies (KF5, +)
+          apt-get -y install \
+            libkf5config-dev \
+            libkf5coreaddons-dev \
+            libkf5i18n-dev \
+            libkf5iconthemes-dev \
+            libkf5parts-dev \
+            libkf5service-dev \
+            libkf5solid-dev \
+            libkf5crash-dev \
+            libkf5package-dev \
+            libkf5plasma-dev \
+            libpwquality-dev \
+            libqt5webenginewidgets5 \
+            qtwebengine5-dev
       - name: "prepare source"
         uses: calamares/actions/generic-checkout@v4
       - name: "build"