Do not fuzz gc-atomics.wast (#7211)

The interpreter does not yet support the struct RMW ops, so this test
file cannot be fuzzed.

Author: tlively

scripts/test/fuzzing.py

@@ -75,6 +75,8 @@
     'typed_continuations_contnew.wast',
     'typed_continuations_contbind.wast',
     'typed_continuations_suspend.wast',
+    # the fuzzer does not support struct RMW ops
+    'gc-atomics.wast',
     # contains too many segments to run in a wasm VM
     'limit-segments_disable-bulk-memory.wast',
     # https://github.com/WebAssembly/binaryen/issues/7176