Set flaky=True on roleserve_test and memory_test

These are frequent CI failures.

Change-Id: Ic45f4dcd22bb608bc96da84c9de74faae1f8daab
Reviewed-on: https://review.monogon.dev/c/monogon/+/1953
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
Tested-by: Jenkins CI
diff --git a/metropolis/pkg/event/memory/BUILD.bazel b/metropolis/pkg/event/memory/BUILD.bazel
index d8c1990..c8a8bae 100644
--- a/metropolis/pkg/event/memory/BUILD.bazel
+++ b/metropolis/pkg/event/memory/BUILD.bazel
@@ -15,4 +15,6 @@
         "memory_test.go",
     ],
     embed = [":memory"],
+    # TODO: https://github.com/monogon-dev/monogon/issues/127
+    flaky = True,
 )