Rollup merge of #130151 - ChrisDenton:slow-ci, r=Mark-Simulacrum

Use a small runner for msvc-ext2 job

Hopefully this should eliminate the errors from this job. The only question is how long it takes.

try-job: x86_64-msvc-ext2

src/ci/github-actions/jobs.yml

@@ -24,6 +24,10 @@ runners:
     os: macos-14
     <<: *base-job
 
+  - &job-windows
+    os: windows-2022
+    <<: *base-job
+
   - &job-windows-8c
     os: windows-2022-8core-32gb
     <<: *base-job
@@ -388,7 +392,7 @@ auto:
         python x.py miri --stage 2 library/alloc --test-args notest &&
         python x.py miri --stage 2 library/std --test-args notest
       RUST_CONFIGURE_ARGS: --build=x86_64-pc-windows-msvc --enable-lld
-    <<: *job-windows-8c
+    <<: *job-windows
 
   # 32/64-bit MinGW builds.
   #