increase windows CI timeout from 20 to 30 minutes (#3903)

This is intended to avoid the timeout issue happening in the private
staging repo

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.github/workflows/ci.yml

@@ -203,7 +203,7 @@ jobs:
   test-rust-windows:
     name: Rust Tests on Windows
     runs-on: windows-latest
-    timeout-minutes: 20
+    timeout-minutes: 30
     env:
       # Disable incremental compilation to reduce disk space use
       CARGO_INCREMENTAL: 0