[wasm] Skip flaky asm-wasm-{switch,expr} on gc-stress

BUG=v8:5716
R=machenbach@chromium.org
NOTRY=true
CC=titzer@chromium.org, bradnelson@chromium.org

Review-Url: https://codereview.chromium.org/2554023002
Cr-Commit-Position: refs/heads/master@{#41517}

test/mjsunit/mjsunit.status

@@ -245,6 +245,10 @@
 
   #BUG(v8:5683)
   'wasm/import-memory': [SKIP],
+
+  #BUG(v8:5716)
+  'wasm/asm-wasm-switch': [SKIP],
+  'wasm/asm-wasm-expr': [SKIP],
 }],  # 'gc_stress == True'
 
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