use ByteStringInputStream #834

Job	Run time
Checks	2m 7s
Docs	2m 44s
Compile and test (2.12.19, 8)	4m 8s
Compile Benchmarks	1m 46s
Compile and test (2.12.19, 11)	4m 0s
Gradle tests	3m 35s
Compile and test (2.12.19, 17)	4m 22s
Maven tests	2m 43s
Compile and test (2.13.13, 8)	4m 28s
sbt scripted tests (gen-scala-server, 2.12)	8m 12s
sbt scripted tests (gen-java, 2.12)	3m 48s
Compile and test (2.13.13, 11)	4m 47s
Compile and test (2.13.13, 17)	4m 53s
Compile and test (3.3.3, 8)	4m 40s
Compile and test (3.3.3, 11)	5m 2s
Compile and test (3.3.3, 17)	5m 8s
	1h 6m 23s

Provide feedback