chore: fix dependabot file (#1834)

Co-authored-by: Felix Angelov <[email protected]>

Author: renancaraujo

.github/dependabot.yaml

@@ -4,25 +4,16 @@ updates:
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "weekly"
+      interval: "monthly"
     groups:
       gh-deps:
         patterns:
           - "*"
-  # Dart Dependencies
-  - package-ecosystem: "pub"
-    directory: "/"
-    schedule:
-      interval: "weekly"
-    groups:
-      dart-deps:
-        patterns:
-          - "*"
   # NPM Dependencies
   - package-ecosystem: "npm"
     directory: "/extensions/vscode"
     schedule:
-      interval: "weekly"
+      interval: "monthly"
     ignore:
       # Updating @types/vscode requires unnecessarily bumping the VS Code engine version, see:
       # https://github.com/dart-frog-dev/dart_frog/issues/1033
@@ -34,8 +25,26 @@ updates:
   - package-ecosystem: "npm"
     directory: "/docs"
     schedule:
-      interval: "weekly"
+      interval: "monthly"
     groups:
       npm-deps:
         patterns:
           - "*"
+  # Dart Dependencies
+  - package-ecosystem: pub
+    directories:
+      - /packages/dart_frog
+      - /packages/dart_frog_auth
+      - /packages/dart_frog_cli/e2e
+      - /packages/dart_frog_cli
+      - /packages/dart_frog_gen
+      - /packages/dart_frog_lint
+      - /packages/dart_frog_test/example
+      - /packages/dart_frog_test
+      - /packages/dart_frog_web_socket
+    schedule:
+      interval: monthly
+    groups:
+      dart-deps:
+        patterns:
+          - "*"