CI: Scale back targets in test matrix.

The matrix was too large for GitHub Actions to process.

.github/workflows/ci.yml

@@ -167,26 +167,12 @@ jobs:
           - target: aarch64-unknown-linux-gnu
             host_os: ubuntu-22.04
 
-          - target: aarch64-unknown-linux-musl
-            host_os: ubuntu-22.04
-
-          - target: arm-unknown-linux-gnueabi
-            host_os: ubuntu-22.04
-
-          - target: armv7-linux-androideabi
-            host_os: ubuntu-22.04
-            # TODO: https://github.com/briansmith/ring/issues/838
-            cargo_options: --no-run
-
           - target: armv7-unknown-linux-musleabihf
             host_os: ubuntu-22.04
 
           - target: i686-pc-windows-msvc
             host_os: windows-latest
 
-          - target: i686-unknown-linux-gnu
-            host_os: ubuntu-22.04
-
           - target: i686-unknown-linux-musl
             host_os: ubuntu-22.04
 
@@ -199,18 +185,12 @@ jobs:
           - target: wasm32-wasi
             host_os: ubuntu-22.04
 
-          - target: x86_64-pc-windows-gnu
-            host_os: windows-latest
-
           - target: x86_64-pc-windows-msvc
             host_os: windows-latest
 
           - target: x86_64-apple-darwin
             host_os: macos-13
 
-          - target: x86_64-unknown-linux-musl
-            host_os: ubuntu-22.04
-
           - target: x86_64-unknown-linux-gnu
             host_os: ubuntu-22.04