use Pekko JavaConverter #1032

Job	Run time
Checks	1m 33s
Checks	1m 33s
Compile Benchmarks	1m 5s
Compile Benchmarks	1m 5s
Docs	2m 18s
Docs	2m 18s
Gradle tests	3m 3s
Gradle tests	3m 3s
Compile and test (2.12.20, 8)	3m 57s
Compile and test (2.12.20, 8)	3m 57s
Maven tests	2m 39s
Maven tests	2m 39s
Compile and test (2.12.20, 11)	3m 51s
Compile and test (2.12.20, 11)	3m 51s
sbt scripted tests (gen-scala-server, 2.12)	7m 59s
sbt scripted tests (gen-scala-server, 2.12)	7m 59s
Compile and test (2.12.20, 17)	4m 6s
Compile and test (2.12.20, 17)	4m 6s
sbt scripted tests (gen-java, 2.12)	3m 41s
sbt scripted tests (gen-java, 2.12)	3m 41s
Compile and test (2.12.20, 21)	3m 53s
Compile and test (2.12.20, 21)	3m 53s
Compile and test (2.13.15, 8)	4m 39s
Compile and test (2.13.15, 8)	4m 39s
Compile and test (2.13.15, 11)	4m 19s
Compile and test (2.13.15, 11)	4m 19s
Compile and test (2.13.15, 17)	4m 35s
Compile and test (2.13.15, 17)	4m 35s
Compile and test (2.13.15, 21)	4m 34s
Compile and test (2.13.15, 21)	4m 34s
Compile and test (3.3.4, 8)	4m 33s
Compile and test (3.3.4, 8)	4m 33s
Compile and test (3.3.4, 11)	4m 26s
Compile and test (3.3.4, 11)	4m 26s
Compile and test (3.3.4, 17)	4m 53s
Compile and test (3.3.4, 17)	4m 53s
Compile and test (3.3.4, 21)	3m 43s
Compile and test (3.3.4, 21)	4m 18s
	2h 28m 9s

Provide feedback