Enable Dependabot updates for vcpkg

JamieMagee · hsbt · commit f7687c4a513d · 2025-08-20T13:10:02.000+09:00
See https://github.blog/changelog/2025-08-12-dependabot-version-updates-now-support-vcpkg/
diff --git a/.github/dependabot.yml b/.github/dependabot.yml
@@ -16,3 +16,7 @@ updates:
     directory: '/yjit'
     schedule:
       interval: 'daily'
+  - package-ecosystem: 'vcpkg'
+    directory: '/'
+    schedule:
+      interval: 'daily'
