[test] Skip slow test in stress mode

TBR=yangguo@chromium.org
NOTRY=true

Change-Id: I2138299e93f5790118d1b28ddf7f4c8219f5831d
Reviewed-on: https://chromium-review.googlesource.com/439564Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#43037}

test/debugger/debugger.status

@@ -33,6 +33,9 @@
   # TODO(jarin/mstarzinger): Functions with eval or debugger now get optimized
   # with Turbofan, which has issues with the debugger issues.
   'debug/debug-evaluate-locals': [FAIL],
+
+  # Very slow in stress mode.
+  'regress/regress-2318': [SKIP],
 }],  # 'stress == True'
 
 ##############################################################################