[TRY] use the new windows-11-arm runners for aarch64-pc-windows-msvc

Author: sayantn

.github/workflows/main.yml

@@ -114,7 +114,7 @@ jobs:
         - tuple: i686-pc-windows-msvc
           os: windows-2025
         - tuple: aarch64-pc-windows-msvc
-          os: windows-2025
+          os: windows-11-arm
         - tuple: x86_64-pc-windows-gnu
           os: windows-2025
         # - tuple: i686-pc-windows-gnu
@@ -193,10 +193,6 @@ jobs:
             tuple: aarch64-apple-ios-macabi
             os: macos-15
           norun: true # https://github.com/rust-lang/stdarch/issues/1206
-        - target:
-            tuple: aarch64-pc-windows-msvc
-            os: windows-2025
-          norun: true
 
     steps:
     - uses: actions/checkout@v4
@@ -205,6 +201,11 @@ jobs:
       run: |
         rustup update nightly --no-self-update
         rustup default nightly
+      if: matrix.target.os != 'windows-11-arm'
+    - name: Install Rust in `windows-11-arm` runners # FIXME: currently the `windows-11-arm` runners don't come with rustup
+      uses: dtolnay/rust-toolchain@nightly
+      if: matrix.target.os == 'windows-11-arm'
+
     - run: rustup target add ${{ matrix.target.tuple }}
       if: matrix.build_std == ''
     - run: |