Forward signals to child process

Required also a small refactoring of the timeout logic. Begin to add
the --node-exporter-dir option.
7 jobs for master in 1 minute and 33 seconds
Status Job ID Name Coverage
  Build
failed #4098
build

00:01:33

 
  Test
skipped #4100
allowed to fail
code_quality
skipped #4104
allowed to fail
container_scanning
skipped #4103
allowed to fail
dependency_scanning
skipped #4101
allowed to fail
license_management
skipped #4102
allowed to fail
sast
skipped #4099
test
 
Name Stage Failure
failed
build Build
5ac34e15ac7b: Pull complete
7ff3cba3e710: Pull complete
8be7609fa05c: Pull complete
28b563a2d870: Pull complete
7d2ba817ef0b: Pull complete
Digest: sha256:d1581d20408be7a7366b6ea74dc5cddc866f4ad4c573a04251272471c0aa2e56
Status: Downloaded newer image for gliderlabs/herokuish:latest
-----> Unable to select a buildpack
ERROR: Job failed: exit code 1