bugfix: Try to fix Mill flaky test #11456

Job	Run time
windows-latest jdk-17 unit tests 1 / 2	32m 0s
windows-latest jdk-17 unit tests 2 / 2	27m 16s
Gradle MacOS integration	13m 3s
macOS-latest jdk-17 unit tests 1 / 2	23m 6s
Sbt integration	1h 3m 50s
macOS-latest jdk-17 unit tests 2 / 2	1h 20m 16s
Maven integration	8m 33s
ubuntu-latest jdk-17 unit tests 1 / 2	16m 55s
Gradle integration	9m 11s
ubuntu-latest jdk-17 unit tests 2 / 2	20m 20s
Scala CLI integration	14m 37s
ubuntu-latest jdk-8 unit tests 1 / 2	25m 6s
Mill integration	12m 11s
ubuntu-latest jdk-8 unit tests 2 / 2	21m 31s
LSP integration tests	32m 22s
Scala cross tests	1h 16m 20s
Formatting	1m 24s
Scalafix and docs	10m 1s
Sbt-metals/scripted jdk8	1m 59s
Scala javapc tests	2m 25s
Scala3 latest NIGHTLY cross test	5m 27s
MiMa	1m 12s
	8h 19m 5s

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