test: remove flaky mark for test-debug-no-context

test-debug-no-context flakiness was worked around in issue 5269 but the
flaky designation was left for the test. This change removes it.

Refs: https://github.com/nodejs/node/pull/5269
PR-URL: https://github.com/nodejs/node/pull/5317
Reviewed-By: Evan Lucas <evanlucas@me.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/parallel/parallel.status

@@ -7,7 +7,6 @@ prefix parallel
 [true] # This section applies to all platforms
 
 [$system==win32]
-test-debug-no-context   : PASS,FLAKY
 test-tls-ticket-cluster : PASS,FLAKY
 test-tick-processor     : PASS,FLAKY