[Java] Switch to Java 17 (#11)

* [Java] Switch to Java 17
Also set UTF-8 explicitly to get rid of some warnings.

* Apparently forgot this entry with the previous PR

* Updated maven-plugin-plugin to a JDK 17 version

.github/workflows/on-pull_request-opened-synchronize-reopened.yml

@@ -16,8 +16,6 @@ jobs:
           path: aerius-github-actions
           ref: v1.1
 
-      - uses: aerius/github-actions/events/pull_request-event-action@v1.0.2
+      - uses: aerius/github-actions/events/pull_request-event-action@v1.1
         with:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-          JDK_VERSION: 11
-

.github/workflows/on-push.yml

@@ -21,5 +21,4 @@ jobs:
           SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
           NEXUS_USERNAME: ${{ secrets.NEXUS_USERNAME }}
           NEXUS_PASSWORD: ${{ secrets.NEXUS_PASSWORD }}
-          JDK_VERSION: 11
 

.github/workflows/on-release-published.yml

@@ -22,5 +22,4 @@ jobs:
           SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
           NEXUS_USERNAME: ${{ secrets.NEXUS_USERNAME }}
           NEXUS_PASSWORD: ${{ secrets.NEXUS_PASSWORD }}
-          JDK_VERSION: 11
 

pom.xml

@@ -56,10 +56,12 @@
   </distributionManagement>
 
   <properties>
-    <maven.compiler.source>11</maven.compiler.source>
-    <maven.compiler.target>11</maven.compiler.target>
+    <maven.compiler.source>17</maven.compiler.source>
+    <maven.compiler.target>17</maven.compiler.target>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
 
-    <maven-plugin.version>3.6.0</maven-plugin.version>
+    <maven-plugin.version>3.8.2</maven-plugin.version>
     <junit.version>5.7.2</junit.version>
     <jackson.version>2.12.3</jackson.version>