Export SHA var as it's used during pre-commit itself

bin/pre-commit-diff.sh

@@ -5,7 +5,7 @@
 # feature according to GitLab... so this is a workaround for extracting the hash
 CI_MERGE_REQUEST_TARGET_BRANCH_NAME="${1:-master}"  # Set to master or 1st input
 CI_COMMIT_SHA=$(git rev-parse HEAD)
-CI_MERGE_REQUEST_TARGET_BRANCH_SHA=$(git ls-remote origin $CI_MERGE_REQUEST_TARGET_BRANCH_NAME | cut -d$'\t' -f1)
+export CI_MERGE_REQUEST_TARGET_BRANCH_SHA=$(git ls-remote origin $CI_MERGE_REQUEST_TARGET_BRANCH_NAME | cut -d$'\t' -f1)
 FILES=$(git diff $CI_COMMIT_SHA  $CI_MERGE_REQUEST_TARGET_BRANCH_SHA --name-only | tr '\n' ' ')
 echo "Running pre-commit on diff from  $CI_COMMIT_SHA to $CI_MERGE_REQUEST_TARGET_BRANCH_SHA ($CI_MERGE_REQUEST_TARGET_BRANCH_NAME)"
 #  Pass list of modified files to pre-commit so that it only checks them