Revert "Mark x86 CI as xfail (#2614)"

This reverts commit f44193a.

Author: vchuravy

.github/workflows/CI.yml

@@ -124,7 +124,7 @@ jobs:
           JULIA_PKG_SERVER_REGISTRY_PREFERENCE: eager
       - uses: julia-actions/julia-runtest@v1
         if: matrix.version != 'nightly' || steps.buildpkg.outcome == 'success'
-        continue-on-error: ${{ matrix.version == 'nightly' || matrix.arch == 'x86' }}
+        continue-on-error: ${{ matrix.version == 'nightly' }}
         id: run_tests
         # TODO restore coverage post https://github.com/JuliaGPU/GPUCompiler.jl/pull/711
         with: