Drop experimental chrome_all_tast_tests suite on chromeos-octopus-chrome

The 10 shards of the suite are taking up pool capacity and starving out
the two non-experimental shards:
https://ci.chromium.org/ui/p/chrome/builders/ci/chromeos-octopus-chrome/14954/overview

So this just removes the experimental suite until DUTs stop dropping
offline: b/248270560

Bug: 1293222
Change-Id: I4f7f3e6691b6156c01caf474bbe137072d583c9c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3942928
Reviewed-by: Sven Zheng <[email protected]>
Commit-Queue: Ben Pastene <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1057135}
diff --git a/testing/buildbot/test_suite_exceptions.pyl b/testing/buildbot/test_suite_exceptions.pyl
index 7e9c40a..af43158 100644
--- a/testing/buildbot/test_suite_exceptions.pyl
+++ b/testing/buildbot/test_suite_exceptions.pyl
@@ -1216,10 +1216,11 @@
           'shards': 5,
         }
       },
-      'chromeos-octopus-chrome': {
-        'experiment_percentage': 100,
-      },
     },
+    # TODO(b/248270560): Restore if the DUT pool is ever stabilized.
+    'remove_from': [
+      'chromeos-octopus-chrome',
+    ],
   },
   'chrome_all_tast_tests_with_lacros': {
     'modifications': {