Set git username and API token via settings.xml file.

.travis.settings.xml

@@ -45,6 +45,11 @@
          <username>${env.DOCKERHUB_USERNAME}</username>
          <password>${env.DOCKERHUB_PASSWORD}</password>
       </server>
+      <server>
+         <id>github</id>
+         <username>${env.GITHUB_USERNAME}</username>
+         <password>${env.GITHUB_API_TOKEN}</password>
+      </server>
       <server>
          <id>alfresco-internal</id>
          <username>${env.MAVEN_USERNAME}</username>

scripts/release.sh

@@ -23,8 +23,7 @@ if [ -z ${RELEASE_VERSION} ] || [ -z ${DEVELOPMENT_VERSION} ];
          exit 1
 else
     mvn --batch-mode \
-    -Dusername="${GITHUB_USERNAME}" \
-    -Dpassword="${GITHUB_API_TOKEN}" \
+    -settings .travis.settings.xml \
     -DreleaseVersion=${RELEASE_VERSION} \
     -DdevelopmentVersion=${DEVELOPMENT_VERSION} \
     -DskipTests -D${release_type} -DuseReleaseProfile=false \