Fix heuristics bumping (according to Armin's comments).

4 jobs for master in 4 minutes and 49 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Build
passed #4791
jars-j8

00:00:36

failed #4790
java8

00:04:13

 
  Test
skipped #4793
allowed to fail
java10
skipped #4792
java7
 
Name Stage Failure
failed
java8 Build
233200 [ERROR] 
233200 [ERROR] Re-run Maven using the -X switch to enable full debug logging.
233200 [ERROR]
233200 [ERROR] For more information about the errors and possible solutions, please read the following articles:
233201 [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
233201 [ERROR]
233201 [ERROR] After correcting the problems, you can resume the build with the command
233201 [ERROR] mvn <goals> -rf :org.ow2.sat4j.core
ERROR: Job failed: exit code 1