[test] Unskip fixed test

TBR=mvstanton@chromium.org

Bug: v8:4495
Change-Id: I8a8beb85ec7e28ca98504d811542dff1fced25dc
Reviewed-on: https://chromium-review.googlesource.com/865897Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Reviewed-by: Michael Stanton <mvstanton@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50564}

test/mjsunit/mjsunit.status

@@ -595,9 +595,6 @@
   'math-floor-of-div-nosudiv': [PASS, ['mode == debug', SKIP]],
   'unicodelctest': [PASS, ['mode == debug', SKIP]],
 
-  # BUG(v8:4495).
-  'es6/collections': [PASS, ['arch == ia32', FAST_VARIANTS]],
-
   # Setting the timezone and locale with environment variables unavailable
   'icu-date-to-string': [SKIP],
   'icu-date-lord-howe': [SKIP],