ci: increase prover fmt timeout (#1589)

Author: yiweichi

.github/workflows/prover.yml

@@ -43,7 +43,7 @@ jobs:
       github.event.pull_request.draft == false &&
       (github.event.action == 'ready_for_review' || needs.skip_check.outputs.should_skip != 'true')
     runs-on: ubuntu-latest
-    timeout-minutes: 5
+    timeout-minutes: 15
     steps:
       - uses: actions/checkout@v4
       - uses: dtolnay/rust-toolchain@master