[Object.hasOwn] Add Test262 feature-to-flag mapping

Bug: chromium:1213927
Change-Id: I85f5559863524717355ec61694ce007a2be7c8a5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2931799Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Mathias Bynens <mathias@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74967}

test/test262/testcfg.py

@@ -57,6 +57,8 @@ FEATURE_FLAGS = {
   'regexp-named-groups': '--harmony-regexp-match-indices',
   'error-cause': '--harmony-error-cause',
   'import-assertions': '--harmony-import-assertions',
+  # https://github.com/tc39/test262/pull/2995
+  'Object.hasOwn': '--harmony-object-has-own',
 }
 
 SKIPPED_FEATURES = set([])