fix(test): free the return-type table in the go field-chain helper

run_go_field_chain_sequential tears down the results, registry and
cross arenas but never calls harness_ctx_free_tables, so pass_calls'
CBMReturnTypeTable (strdup'd method return types) leaked whenever the
helper ran. ASan builds caught it: AddressSanitizer: 32911 byte(s)
leaked in 6 allocation(s) from build_return_type_table, failing
test-diag, test-lsan-macos and both gcc sanitizer shards. Verify
locally: build/c/test-runner parallel -> 73 passed, no leaks.

Signed-off-by: xkchok <143325001+xkchok@users.noreply.github.com>

tests/test_parallel.c

@@ -3282,6 +3282,7 @@ static cbm_gbuf_t *run_go_field_chain_sequential(const char *project, const char
         cbm_free_result(cache[i]);
     }
     free(cache);
+    harness_ctx_free_tables(&ctx);
     cbm_registry_free(reg);
     if (ctx.seq_cross_arena_live) {
         cbm_arena_destroy(&ctx.seq_cross_arena);