Enable some miscellaneous GC spec tests

These weren't caught by our checks that `should_fail` tests do not pass, I think
because they only contain modules that should validate, and not any actual
assertions.

tests/wast.rs

@@ -203,17 +203,7 @@ fn should_fail(test: &Path, strategy: Strategy) -> bool {
  }
  }
  }
- let unsupported_gc_tests = [
- "binary_gc.wast",
- "br_on_cast_fail.wast",
- "br_on_cast.wast",
- "table_sub.wast",
- "type_canon.wast",
- "type_equivalence.wast",
- "type-rec.wast",
- "type-subtyping.wast",
- "unreached_valid.wast",
- ];
+ let unsupported_gc_tests = ["type-rec.wast", "type-subtyping.wast"];
 
  for part in test.iter() {
  // Not implemented in Wasmtime yet