Don't check symbol prefixes during test-bench.

This seems to have been accidentally carried over when `test-bench` was
factored out of `test`.

.github/workflows/ci.yml

@@ -382,19 +382,6 @@ jobs:
         run: |
           mk/cargo.sh +${{ matrix.rust_channel }} test -vv --doc --target=${{ matrix.target }} ${{ matrix.cargo_options }} ${{ matrix.features }} ${{ matrix.mode }}
 
-      # Check that all the needed symbol renaming was done.
-      # TODO: Do this check on Windows too.
-      # TODO: Check iOS too.
-      # TODO: Do this on Apple-hosted release builds too; currently these fail with:
-      #       Unknown attribute kind (528)
-      #       (Producer: 'LLVM12.0.0-rust-1.54.0-nightly'
-      #       Reader: 'LLVM APPLE_1_1200.0.32.29_0')
-      - if: ${{ matrix.target != 'aarch64-apple-ios' &&
-          !contains(matrix.host_os, 'windows') &&
-          (!contains(matrix.host_os, 'macos') || matrix.mode != '--release') }}
-        run: mk/check-symbol-prefixes.sh --target=${{ matrix.target }}
-
-
   # The wasm32-unknown-unknown targets have a different set of feature sets and
   # an additional `webdriver` dimension.
   test-wasm32-browser: