`TopicSuite` is flaking frequently

[armanbilge]

==> X fs2.concurrent.TopicSuite.unregister subscribers under concurrent load  0.035s munit.ComparisonFailException: /home/runner/work/fs2/fs2/core/shared/src/test/scala/fs2/concurrent/TopicSuite.scala:113
112:        .map { result =>
113:          assertEquals(result.toMap.size, subs / 2)
114:          assertEquals(result.toMap, expected)
values are not the same
=> Obtained
6
=> Diff (- obtained, + expected)
-6
+5

[armanbilge]

Does anyone know if this test is about concurrent load, or parallel load? If it only needs concurrency, and not true parallelism, it looks like a good candidate for executeEmbed(...) to avoid the flakiness.