Create dependabot.yml (#1)

.github/dependabot.yml

@@ -0,0 +1,34 @@
+version: 2
+updates:
+
+  - package-ecosystem: "github-actions"
+    # Workflow files stored in the
+    # default location of `.github/workflows`
+    directory: "/"
+    schedule:
+      interval: "monthly"
+
+  - package-ecosystem: "gitsubmodule"
+    directory: "external/common_items"
+    schedule:
+      interval: "daily"
+
+  - package-ecosystem: "gitsubmodule"
+    directory: "external/fmt"
+    schedule:
+      interval: "monthly"
+
+  - package-ecosystem: "gitsubmodule"
+    directory: "external/bitmap"
+    schedule:
+      interval: "monthly"
+
+  - package-ecosystem: "gitsubmodule"
+    directory: "external/Fronter"
+    schedule:
+      interval: "daily"
+
+  - package-ecosystem: "gitsubmodule"
+    directory: "/"
+    schedule:
+      interval: "monthly"