Make actions much faster, only run checks for pushes on master branch. (#122)

Author: TheGlitch76

.github/workflows/build.yml

@@ -2,37 +2,63 @@ name: Java CI
 
 on:
   push:
+    branches:
+      - master
   pull_request:
+
 jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - uses: actions/setup-java@v1
         with:
           java-version: 8
+      # https://github.com/actions/cache/blob/master/examples.md#java---gradle
+      - uses: actions/cache@v2
+        with:
+          path: ~/.gradle/caches
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
+          restore-keys: |
+            ${{ runner.os }}-gradle-
       - uses: eskatos/gradle-command-action@v1
         with:
-          arguments: build -x checkstyleMain -x checkLicenses
+          arguments: remapJar
+      # Artifact publishing
+      - uses: actions/upload-artifact@v2
+        with:
+          path: ./build/libs/patchwork-api-?.?.?.jar
 
   checkstyle:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - uses: actions/setup-java@v1
         with:
           java-version: 8
+      - uses: actions/cache@v2
+          with:
+            path: ~/.gradle/caches
+            key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
+            restore-keys: |
+              ${{ runner.os }}-gradle-
       - uses: eskatos/gradle-command-action@v1
         with:
           arguments: checkstyleMain
 
   license:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v1
+      - uses: actions/checkout@v2
       - uses: actions/setup-java@v1
         with:
           java-version: 8
+      - uses: actions/cache@v2
+          with:
+            path: ~/.gradle/caches
+            key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*') }}
+            restore-keys: |
+              ${{ runner.os }}-gradle-
       - uses: eskatos/gradle-command-action@v1
         with:
           arguments: checkLicenses