Update README.md: ACTS v15.1+

7 jobs for master in 12 minutes and 54 seconds (queued for 1 second)
Name Stage Failure
juggler:default Docker
65bf54e5e2b1: Retrying in 1 second
65bf54e5e2b1: Pushed
net/http: TLS handshake timeout
Docker push failed, retrying in 80 seconds...
docker rmi eicweb.phy.anl.gov:4567/eic/juggler/juggler:testing
Untagged: eicweb.phy.anl.gov:4567/eic/juggler/juggler:testing
Failed to push eicweb.phy.anl.gov:4567/eic/juggler/juggler:testing-4.3.0 to eicweb.phy.anl.gov:4567/eic/juggler/juggler:testing
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1