[wasm] Reenable test-run-wasm/I64*OnDifferentRegisters tests

After https://crrev.com/c/995533, the tests should be stable again.

R=ahaas@chromium.org

Bug: v8:7621
Change-Id: Ib7a6a6503cb5398c179937a68daace09f43b9b3a
Reviewed-on: https://chromium-review.googlesource.com/995443
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#52375}

test/cctest/cctest.status

@@ -133,10 +133,6 @@
   'test-serialize/StartupSerializerTwice': [SKIP],
   'test-serialize/StartupSerializerOnceRunScript': [SKIP],
   'test-serialize/StartupSerializerTwiceRunScript': [SKIP],
-
-  # Flaky test
-  'test-run-wasm/RunWasmLiftoff_I64ShrSOnDifferentRegisters': [SKIP],
-  'test-run-wasm/RunWasmTurbofan_I64ShlOnDifferentRegisters': [SKIP],
 }],  # ALWAYS
 
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