fix: resolve shellcheck warnings (SC2168, SC2089, SC2090, SC2016, SC2329)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

phase2_gitea_fedora.sh

@@ -53,10 +53,12 @@ _set_db_vars() {
       DB_DOCKER_IMAGE="mcr.microsoft.com/mssql/server:2022-latest"
       DB_ENV_VARS="      - ACCEPT_EULA=Y
       - SA_PASSWORD=${GITEA_DB_PASSWD}"
+      # shellcheck disable=SC2089,SC2016
       DB_HEALTHCHECK='["CMD-SHELL", "/opt/mssql-tools18/bin/sqlcmd -S localhost -U sa -P '"'"'${GITEA_DB_PASSWD}'"'"' -Q \"SELECT 1\" -C -N"]'
       DB_DATA_DIR="mssql/data"
       ;;
   esac
+  # shellcheck disable=SC2090
   export DB_DOCKER_IMAGE DB_ENV_VARS DB_HEALTHCHECK DB_DATA_DIR
 }