Add Pull Request Build Action

This commit adds PR.yml which is a GitHub action that will try and build the PR being submitted to make sure it can be built and also to help people beta-testing PRs and hopefully saving everyone time! The built jar files are then uploaded as artifacts of the action in a easy to download .zip file!

.github/workflows/PR.yml

@@ -0,0 +1,35 @@
+name: Pull Request Actions
+on:
+  pull_request:
+
+jobs:
+  Build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v3
+
+      - name: Setup JDK 17
+        uses: actions/setup-java@v3
+        with:
+          java-version: '17'
+          distribution: temurin
+
+      - name: Setup Gradle
+        uses: gradle/gradle-build-action@v2
+
+      - name: Validate Gradle Wrapper Integrity
+        uses: gradle/wrapper-validation-action@v1
+
+      - name: Make Gradle wrapper executable
+        run: chmod +x ./gradlew
+
+      - name: Build
+        run: ./gradlew build
+
+      - name: Publish Artifacts on GitHub Actions
+        uses: actions/upload-artifact@v3   
+        with:
+          if-no-files-found: error
+          path: build/libs/
+          name: CEI .jar files from PR