fix: ignore tj-actions from frequent updates (#241)

Author: wtrocki

.github/dependabot.yml

@@ -8,7 +8,7 @@ updates:
   - package-ecosystem: github-actions
     directory: "/"
     schedule:
-      interval: weekly
+      interval: monthly
       day: monday
     reviewers:
       - "mongodb/APIx1"
@@ -18,4 +18,4 @@ updates:
       interval: weekly
       day: monday
     reviewers:
-      - "mongodb/APIx1"
+      - "mongodb/APIx1"