fix(ci): drop aarch64-linux wheel — ring manylinux2014 cross-compile unfixable

ring 0.17 ASM incompatible with GCC10 manylinux2014 cross-toolchain.
Linux arm64 users: cargo install devsper-bin.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: rithulkamesh

.github/workflows/publish.yml

@@ -99,8 +99,6 @@ jobs:
         include:
           - os: ubuntu-latest
             target: x86_64-unknown-linux-gnu
-          - os: ubuntu-latest
-            target: aarch64-unknown-linux-gnu
           - os: macos-latest
             target: x86_64-apple-darwin
           - os: macos-latest
@@ -111,10 +109,6 @@ jobs:
     steps:
       - uses: actions/checkout@v4
 
-      - name: Set ARM64 cross-compile flags (ring requires __ARM_ARCH)
-        if: matrix.target == 'aarch64-unknown-linux-gnu'
-        run: echo "CFLAGS_aarch64_unknown_linux_gnu=-march=armv8-a" >> $GITHUB_ENV
-
       - uses: PyO3/maturin-action@v1
         with:
           target: ${{ matrix.target }}