Add github actions test

.github/workflows/rubocop.yml

@@ -1,10 +1,10 @@
 name: Run RuboCop
-
-on: [push]
+on:
+  push:
+  pull_request:
 
 jobs:
-  build:
-
+  test:
     runs-on: ubuntu-latest
 
     steps:

.github/workflows/tests.yml

@@ -0,0 +1,29 @@
+name: Run Tests
+on:
+  push:
+  pull_request:
+  schedule:
+    - cron: '0 5 * * *'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        redmine:
+          - v4.0
+          - v4.1
+          - trunk
+        ruby:
+          - v2.4
+          - v2.5
+          - v2.6
+
+    steps:
+      - name: Redmine plugin test
+        uses: two-pack/redmine-plugin-test-action@v2
+        with:
+          plugin_name: redmine_messenger
+          redmine_version: ${{ matrix.redmine }}
+          ruby_version: ${{ matrix.ruby }}