Backport sources to Java 8

Author: vadeg

.github/workflows/workflow.yml

@@ -29,10 +29,10 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - name: Set up JDK 11
+    - name: Set up JDK
       uses: actions/setup-java@v1
       with:
-        java-version: 11
+        java-version: 8
     - name: Cache local Maven repository
       uses: actions/cache@v2
       with:

pom.xml

@@ -59,8 +59,8 @@
 
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-        <maven.compiler.source>11</maven.compiler.source>
-        <maven.compiler.target>11</maven.compiler.target>
+        <maven.compiler.source>8</maven.compiler.source>
+        <maven.compiler.target>8</maven.compiler.target>
         <spring.version>5.3.23</spring.version>
         <postgresql.version>42.5.0</postgresql.version>
         <dependency-check-maven.version>7.2.1</dependency-check-maven.version>