Prevent composer package tests on master branch (#198)

Exclude running the "Test as composer package" step on the master branch
to streamline CI/CD workflows and reduce redundant checks. This change
ensures that these tests only run on feature branches, optimizing build
times and resource usage.

.github/workflows/main.yml

@@ -179,6 +179,7 @@ jobs:
           ! $BLUEPRINT $CMD_VALIDATE $INVALID_TEST
 
       - name: Test as composer package
+        if: github.ref != 'refs/heads/master'
         run: |
           mkdir -pv ./build/composer-test
           cd ./build/composer-test