ci: fix linking issue on windows gnu jobs

.github/workflows/windows.yml

@@ -14,7 +14,7 @@ jobs:
       # There's a limit of 60 concurrent jobs across all repos in the rust-lang organization.
       # In order to prevent overusing too much of that 60 limit, we throttle the
       # number of rustfmt jobs that will run concurrently.
-      max-parallel: 1
+      max-parallel: 2
       fail-fast: false
       matrix:
         target: [
@@ -50,6 +50,17 @@ jobs:
         profile: minimal
         default: true
 
+    - name: Add mingw32 to path for i686-gnu
+      run: |
+        echo "C:\msys64\mingw32\bin" >> $GITHUB_PATH
+      if: matrix.target == 'i686-pc-windows-gnu' && matrix.channel == 'nightly'
+      shell: bash
+
+    - name: Add mingw64 to path for x86_64-gnu
+      run: echo "C:\msys64\mingw64\bin" >> $GITHUB_PATH
+      if: matrix.target == 'x86_64-pc-windows-gnu' && matrix.channel == 'nightly'
+      shell: bash
+
     - name: cargo-make
       run: cargo install --force cargo-make