blast_repo fixes (dart-lang/package_config#135)

dependabot
diff --git a/pkgs/package_config/.github/dependabot.yml b/pkgs/package_config/.github/dependabot.yml
index b2f1dec..c84404d 100644
--- a/pkgs/package_config/.github/dependabot.yml
+++ b/pkgs/package_config/.github/dependabot.yml
@@ -8,3 +8,5 @@
   directory: /
   schedule:
     interval: monthly
+  labels:
+    - autosubmit