[bazel] Use "moderate" timeout for opt_fold_test (KhronosGroup#6553)

It hovers around 60s on Intel-based Mac.

Fixed: KhronosGroup#6552

Author: dneto0

BUILD.bazel

@@ -546,6 +546,7 @@ cc_library(
 [cc_test(
     name = "opt_{testcase}_test".format(testcase = f[len("test/opt/"):-len("_test.cpp")]),
     size = "small",
+    timeout = "moderate" if f[len("test/opt/"):-len("_test.cpp")] == "fold" else "short",
     srcs = [f],
     copts = TEST_COPTS,
     linkstatic = 1,