configure linker via env var insread of .cargo/config.toml

someone might already have a .cargo/config.toml

.cargo/config.toml

@@ -1,2 +0,0 @@
-[target.s390x-unknown-linux-gnu]
-linker = "/usr/bin/s390x-linux-gnu-gcc"

.github/actions/setup-rust/action.yml

@@ -35,13 +35,14 @@ runs:
       sudo apt-get install libssl-dev:i386 gcc-multilib clang -y
       echo "CC=clang" >> $GITHUB_ENV
       echo "PKG_CONFIG_SYSROOT_DIR=/" >> $GITHUB_ENV
-      
+
   - name: Install s390x cross-compilation toolchain
     if: ${{ matrix.target == 's390x-unknown-linux-gnu' }}
     shell: bash
     run: |
       sudo apt-get update
       sudo apt-get install -y gcc-s390x-linux-gnu
+      echo "CARGO_TARGET_S390X_UNKNOWN_LINUX_GNU_LINKER=s390x-linux-gnu-gcc" >> $GITHUB_ENV
 
   - uses: actions/cache@668228422ae6a00e4ad889ee87cd7109ec5666a7 # v5.0.4
     with: