ci: ShellCheck preprocessed scripts separately

Change the shellcheck job so that we configure the build and check the
preprocessed versions of the scripts, not the bare ones, which might not
be syntactically valid yet.

.gitlab-ci.yml

@@ -458,8 +458,15 @@ shellcheck:
   extends:
     - .build_on_fedora
   stage: analysis
+  variables:
+    MESON_OPTIONS: >-
+        -Dpipewire-v4l2=enabled
+        -Dpipewire-jack=enabled
   script:
-    - shellcheck $(git grep -l "#\!/.*bin/.*sh")
+    - echo "Configuring with meson options $MESON_OPTIONS"
+    - meson setup "$BUILD_DIR" --prefix="$PREFIX" $MESON_OPTIONS
+    - shellcheck $(git ls-files '*.sh')
+    - shellcheck $(grep -rl "#\!/.*bin/.*sh" "$BUILD_DIR")
 
 spellcheck:
   extends: