Update comment for dependency grouping in config

Author: limonte

.github/dependabot.yml

@@ -9,7 +9,7 @@ updates:
     directory: '/'
     schedule:
       interval: 'weekly'
-    # group deps
+    # group all deps
     groups:
       dependencies:
         update-types:
@@ -18,7 +18,6 @@ updates:
           - 'patch'
     # do not update if a dependency’s release falls within its cooldown period (same as minimumReleaseAge or stabilityDays)
     cooldown:
-      default-days: 5
       semver-major-days: 30
       semver-minor-days: 7
       semver-patch-days: 7