ci: speed up flutter clone

Author: adil192

.github/shared_workflows/setup_flutter/action.yml

@@ -20,22 +20,31 @@ runs:
         echo "FLUTTER_HASH=${ENGINE_VERSION}-${FLUTTER_PACKAGES_VERSION}" >> $GITHUB_ENV
 
     - name: Cache Flutter
+      id: cache-flutter
       uses: actions/cache@v4
       with:
         path: |
           submodules/flutter/**/.dart_tool
           submodules/flutter/**/bin/cache
-          submodules/flutter/version
         key: ${{ runner.os }}-flutter-${{ env.FLUTTER_HASH }}
 
     - name: Cache Pub
+      id: cache-pub
       uses: actions/cache@v4
       with:
         path: submodules/flutter/.pub-cache
         key: ${{ runner.os }}-pub-${{ env.FLUTTER_HASH }}-${{ hashFiles('**/pubspec.lock') }}
         restore-keys: |
           ${{ runner.os }}-pub-${{ env.FLUTTER_HASH }}-
 
+    - name: Restore Flutter version information
+      shell: bash
+      run: |
+        FLUTTER_VERSION=$(cat ${{ github.workspace }}/submodules/.flutter-version)
+        echo "$FLUTTER_VERSION" > ${{ github.workspace }}/submodules/flutter/version
+        git -C submodules/flutter tag -f stable
+        git -C submodules/flutter tag -f "$FLUTTER_VERSION"
+
     - name: Pre-download Flutter dependencies
       shell: bash
       run: flutter doctor -v

.github/workflows/tests.yml

@@ -15,7 +15,6 @@ jobs:
         uses: actions/checkout@v5
         with:
           submodules: true
-          fetch-depth: 0
 
       - uses: "./.github/shared_workflows/install_apt_dependencies"
 

scripts/update_flutter_submodule.sh

@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# Update local Flutter SDK
+flutter channel stable
+flutter upgrade
+
 # Update Flutter version used in F-Droid builds
 pushd submodules/flutter
 git fetch origin
@@ -10,4 +14,4 @@ popd
 
 # Update Flutter version used in Linux builds
 FLUTTER_VERSION=$(flutter --version | head -n 1 | awk '{print $2}')
-sed -i -E "s/flutter-version: .*/flutter-version: $FLUTTER_VERSION/" .github/workflows/linux.yml
+echo "$FLUTTER_VERSION" > submodules/.flutter-version

submodules/.flutter-version

@@ -0,0 +1 @@
+3.35.3