* fixed #297 try out java15

Author: thomaswoehlke

.github/workflows/maven.yml

@@ -16,9 +16,9 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 13
+    - name: Set up JDK 15
       uses: actions/setup-java@v1
       with:
-        java-version: 13
+        java-version: 15
     - name: Build with Maven
       run: ./mvnw -B -DskipTests clean dependency:purge-local-repository dependency:resolve dependency:resolve-plugins dependency:sources dependency:tree package spring-boot:repackage site --file pom.xml