Set up Github Actions pipeline for PRs

Author: elliedori

.github/workflows/pr-build-workflow.yml

@@ -0,0 +1,28 @@
+name: 2.3.x PR Build
+
+on:
+  pull_request:
+    branches:
+      - 2.3.x
+
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        jdk: [8, 11]
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up JDK ${{ matrix.jdk }}
+        uses: actions/setup-java@v1
+        with:
+          java-version: ${{ matrix.jdk }}
+      - name: Cache Gradle packages
+        uses: actions/cache@v2
+        with:
+          path: ~/.gradle/caches
+          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle') }}
+      - name: Build with Gradle
+        run: ./gradlew clean build --no-daemon --stacktrace

.travis.yml

@@ -1,6 +1,6 @@
 = Spring Session
 
-image:https://travis-ci.org/spring-projects/spring-session.svg?branch=master["Build Status", link="https://travis-ci.org/spring-projects/spring-session"] image:https://badges.gitter.im/spring-projects/spring-session.svg[link="https://gitter.im/spring-projects/spring-session?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge"]
+image:https://badges.gitter.im/spring-projects/spring-session.svg[link="https://gitter.im/spring-projects/spring-session?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge"]
 
 Spring Session provides an API and implementations for managing a user's session information, while also making it trivial to support clustered sessions without being tied to an application container specific solution.
 It also provides transparent integration with: