Skip signing in CI workflow

Change-Id: I4bce8ab097ec1070d4d5411aa76de193227b42af
diff --git a/.github/workflows/ci_test.yml b/.github/workflows/ci_test.yml
index 5d11a93..364b4ec 100644
--- a/.github/workflows/ci_test.yml
+++ b/.github/workflows/ci_test.yml
@@ -18,4 +18,4 @@
       - name: Build and install
         env:
           MAVEN_OPTS: -Xss8m -Xms512m -Xmx4g
-        run: mvn install
+        run: mvn install -Dgpg.skip=true -B -V