Enable submodule checkout in Gradle workflow

Added support for submodules in the checkout step.

Author: Stefterv

.github/workflows/pull_request-gradle.yml

@@ -13,6 +13,8 @@ jobs:
     steps:
       - name: Checkout Repository
         uses: actions/checkout@v4
+        with:
+          submodules: true
       - name: Install Java
         uses: actions/setup-java@v4
         with:
@@ -65,6 +67,8 @@ jobs:
 
       - name: Checkout Repository
         uses: actions/checkout@v4
+        with:
+          submodules: true
       - name: Install Java
         uses: actions/setup-java@v4
         with:
@@ -87,4 +91,4 @@ jobs:
         with:
           name: processing-${{ matrix.os_prefix }}-${{ matrix.arch }}-pr_${{ github.event.pull_request.number }}
           retention-days: 5
-          path: app/build/compose/binaries/main/${{ matrix.binary }}
+          path: app/build/compose/binaries/main/${{ matrix.binary }}