DCO changes

Author: ryanjbaxter

.github/dco.yml

@@ -0,0 +1,2 @@
+require:
+  members: false

.github/workflows/maven.yaml

@@ -4,21 +4,21 @@
 name: Build
 on:
     push:
-        branches: [ main, 3.1.x ]
+        branches: [ main, 4.2.x, 4.1.x, 3.1.x ]
     pull_request:
-        branches: [ main, 3.1.x ]
+        branches: [ main, 4.2.x, 4.1.x, 3.1.x ]
 jobs:
     build:
         runs-on: ubuntu-latest
         steps:
-            - uses: actions/checkout@v2
+            - uses: actions/checkout@v4
             - name: Set up JDK
-              uses: actions/setup-java@v2
+              uses: actions/setup-java@v4
               with:
                   distribution: 'temurin'
                   java-version: '17'
             - name: Cache local Maven repository
-              uses: actions/cache@v2
+              uses: actions/cache@v4
               with:
                   path: ~/.m2/repository
                   key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
@@ -32,7 +32,7 @@ jobs:
               with:
                   report_paths: '**/surefire-reports/TEST-*.xml'
             - name: Archive code coverage results
-              uses: actions/upload-artifact@v2
+              uses: actions/upload-artifact@v4
               with:
                   name: surefire-reports
                   path: '**/surefire-reports/*'

.java-version

@@ -0,0 +1 @@
+17

docs/.java-version

@@ -0,0 +1 @@
+17