message: disable git_sha injection by default, allow override from .lagoon.yml
diff: @@ -18,7 +18,13 @@ else
  /oc-build-deploy/scripts/git-checkout-pull.sh "$SOURCE_REPOSITORY" "$GIT_REF"
  fi
  +INJECT_GIT_SHA=$(cat .lagoon.yml | shyaml get-value environment_variables.git_sha false)
  +if [ "$INJECT_GIT_SHA" == "true" ]
  +then
  LAGOON_GIT_SHA=`git rev-parse HEAD`
  +else
  + LAGOON_GIT_SHA="0000000000000000"
  +fi
  if [[ -n "$SUBFOLDER" ]]; then
  cd $SUBFOLDER
  