Skip header check for merge to main PR (#28)

fix #27

Test run:
https://github.com/YanxuanLiu/spark-rapids/actions/runs/13406205693

---------

Signed-off-by: Yanxuan Liu <[email protected]>

Author: YanxuanLiu

license-header-check/action.yml

@@ -35,6 +35,12 @@ runs:
         # Get license pattern with year
         CURRENT_YEAR=$(date +%Y)
         LICENSE_PATTERN="Copyright \(c\) .*?${CURRENT_YEAR},? NVIDIA CORPORATION."
+
+        # Skip for merge to main PR
+        if [[ "${{ github.event.pull_request.base.ref }}" == "main" ]]; then
+          echo "Skip this check for Merge to main PR."
+          exit 0
+        fi
         
         # Format file patterns
         IFS="," read -r -a INCLUDE_PATTERNS <<< "$(echo "${{ inputs.included_file_patterns }}" | tr -d ' ' | tr -d '\n')"