ci: update GHActions once a month

Apparently some actions like CodeQL are released a few times a week so let's
just update them once a month in one fell swoop.

diff --git a/.github/dependabot.yml b/.github/dependabot.yml
index c6d66e1031a8f02be9f871547b418da96d4cc5e3..3e067c176fd4f9258104336379c8b7b6cf16812a 100644 (file)
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@@ -5,7 +5,7 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "weekly"
+      interval: "monthly"
     open-pull-requests-limit: 2
   - package-ecosystem: "pip"
     directory: "/.github/workflows"