Fix mutants

.github/workflows/mutants.yml

@@ -3,7 +3,6 @@ on:
   pull_request:
     branches: ["main"]
     paths-ignore: ["*.md", "*.png", "*.svg", "LICENSE-*"]
-  merge_group:
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref_name }}
@@ -20,6 +19,16 @@ jobs:
       - name: Relative diff
         run: git diff origin/${{ github.base_ref }}.. > pr.diff
 
+      - name: Install dependencies
+        env:
+          DEBIAN_FRONTEND: noninteractive
+        run: |
+          sudo apt-get install -y --no-install-recommends gyp mercurial ninja-build lld
+          echo "RUSTFLAGS=-C link-arg=-fuse-ld=lld" >> "$GITHUB_ENV"
+
+      - name: Fetch and build NSS and NSPR
+        uses: ./.github/actions/nss
+
       - name: Install Rust
         uses: ./.github/actions/rust
         with: