Disables gvisor test proc_pid_oomscore_test

Depending on runner this passes or fails.
The test expects to be able to open `/proc/self/oom_score_adj` as writable to adjust the oom score.
This is expected to fail on all three of our runners, but sometimes the solidrun board manages to open it.
Disable as it is a flake. Could be a kernel bug on the solid run board

unittests/gvisor-tests/Disabled_Tests

@@ -67,4 +67,7 @@ timers_test
 
 # these are flaky on x86
 itimer_test
-stat_times_test
+stat_times_test
+
+# This periodically fails on ARM hosts. `PosixError(errno=13 Permission denied) open(/proc/self/oom_score_adj, 0x1, 0)`
+proc_pid_oomscore_test