Create github action workflow to validate release build

.github/workflows/release-build.yml

@@ -0,0 +1,39 @@
+name: Quarkus Release Test Build
+
+on:
+  push:
+    branch:
+      - master
+  schedule:
+    - cron: '0 3 * * 2'
+env:
+  LANG: en_US.UTF-8
+jobs:
+  build:
+    name: "Prepare release"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+        with:
+          ref: master
+      - name: Reclaim Disk Space
+        run: .github/ci-prerequisites.sh
+      - name: Set up JDK 8
+        # Uses sha for added security since tags can be updated
+        uses: joschi/setup-jdk@68381f2c0646f942f70b69f8e81fe10e1ed5d293
+        with:
+          java-version: 8
+      - name: Create maven repo
+        run: mkdir -p ~/release/repository
+      - name: Build and Test
+        run: |
+          mvn --settings .github/mvn-settings.xml \
+            -DskipITs -Dinvoker.skip=true \
+            -Dmaven.repo.local=~/release/repository \
+            clean install
+      - name: test
+        if: always()
+        run: ls ~/release/repository/io/quarkus/quarkus-grpc-protoc-plugin/999-SNAPSHOT
+      - name: test
+        if: always()
+        run: ls ~/release/repository/io/quarkus/quarkus-grpc-protoc-plugin/999-SNAPSHOT

devtools/gradle/build.gradle

@@ -21,6 +21,10 @@ repositories {
         maven {
             url System.properties.get('maven.repo.local')
         }
+    } else if (System.getenv().containsKey('MAVEN_LOCAL_REPO')) {
+        maven {
+            url System.getenv('MAVEN_LOCAL_REPO')
+        }
     } else {
         mavenLocal()
     }