Update pylint.yml

.github/workflows/pylint.yml

@@ -19,7 +19,7 @@ jobs:
         python -m pip install --upgrade pip
         pip install pylint
         echo CI_COMMIT_SHA=${GITHUB_SHA}
-        echo CI_MERGE_REQUEST_TARGET_BRANCH_NAME=${GITHUB_BASE_REF}
+        echo CI_MERGE_REQUEST_TARGET_BRANCH_NAME="master"
         git fetch origin ${CI_MERGE_REQUEST_TARGET_BRANCH_NAME}
         tmp_files=$(git diff --name-only ${CI_COMMIT_SHA} ${CI_MERGE_REQUEST_TARGET_BRANCH_NAME})
         echo "Changed files are $tmp_files"