build(ci): make dependabot run weekly (#40)

It's non-trivial to check-in build changes in npm dependencies bump PRs.
Make dependabot run weekly and will manually check in such changes.

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Signed-off-by: Billy Zha <jinzha1@microsoft.com>

.github/dependabot.yml

@@ -19,12 +19,12 @@ updates:
     # default location of `.github/workflows`
     directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
     labels:
       - "dependencies"
   - package-ecosystem: "npm"
     directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
     labels:
       - "dependencies"