[dependabot] Ignore @types/github-script (#32383)

Author: mikeharder

.github/dependabot.yml

@@ -44,3 +44,5 @@ updates:
       - dependency-name: "@types/node"
       # Updated manually to align with repo microsoft/typespec
       - dependency-name: "prettier"
+      # Points to "github:actions/github-script" since package isn't published to npmjs
+      - dependency-name: "@types/github-script"