Update workflows to JDK 17

Author: sgdc3

.github/workflows/maven.yml

@@ -10,7 +10,7 @@ jobs:
   build_and_test:
     strategy:
       matrix:
-        jdkversion: [11]
+        jdkversion: [17]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3

.travis.yml

@@ -4,10 +4,6 @@ language: java
 
 matrix:
   include:
-  - env:
-    - JDK_VERSION=8
-  - env:
-    - JDK_VERSION=11
   - env:
     - JDK_VERSION=17