configure dependabot for bun ecosystem (#103)

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Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: fuomag9 <1580624+fuomag9@users.noreply.github.com>

.github/dependabot.yml

@@ -17,8 +17,8 @@ updates:
       prefix: "ci"
       include: "scope"
 
-  # NPM dependencies updates
-  - package-ecosystem: "npm"
+  # Bun dependencies updates
+  - package-ecosystem: "bun"
     directory: "/"
     schedule:
       interval: "weekly"