Fixed wrong "-e" on md5 file status check (#10803)

The "-e" flag was not reset properly in the md5 status check
which could lead in some cases to removing output of flake check.

scripts/ci/libraries/_md5sum.sh

@@ -92,7 +92,7 @@ function md5sum::calculate_md5sum_for_all_files() {
             FILES_MODIFIED="true"
         fi
     done
-    set +e
+    set -e
 }
 
 #