Unrolled build for rust-lang#132411

Rollup merge of rust-lang#132411 - MarcoIeni:ci-switch-to-free-runners, r=Kobzol

CI: switch dist-x86_64-musl to free runner

try-job: dist-x86_64-musl

Author: rust-timer

Diff for: src/ci/github-actions/jobs.yml

@@ -205,7 +205,7 @@ auto:
   - image: dist-x86_64-musl
     env:
       CODEGEN_BACKENDS: llvm,cranelift
-    <<: *job-linux-8c
+    <<: *job-linux-4c
 
   - image: dist-x86_64-netbsd
     <<: *job-linux-4c