CI: adding --mu option to one of the VM-built variant

Signed-off-by: Raphael Defosseux <raphael.defosseux@eurecom.fr>
11 jobs for <span class="ref-name">356-compilation-fail-for-256-ue</span> in 0 seconds (queued for 12 minutes and 41 seconds)
Status Job ID Name Coverage
  External
passed Analysis with cppcheck

00:06:36

passed Build UE-ethernet

00:08:36

passed Build basic-sim

00:11:26

passed Build eNb-USRP

00:10:37

passed Build eNb-USRP-CentOS

00:06:03

passed Build eNb-ethernet

00:08:37

passed Build phy-sim

00:07:57

failed Test basic-sim

00:11:38

passed Test phy-sim

00:10:27

passed Test-FDD-Band7

00:28:02

failed Test-TDD-Band40

00:05:00