Clarify MUSICA test phase status with date

Updated the status of MUSICA to include the date.

Author: Neves-P

docs/systems.md

@@ -70,7 +70,7 @@ MareNostrum 5 is the EuroHPC JU supercomputer hosted by the [Barcelona Supercomp
 * VSC-5: [General documentation](https://docs.asc.ac.at/systems/vsc5.html) | [EESSI @ VSC-5](https://docs.asc.ac.at/software/eessi.html)
 * MUSICA: [General documentation](https://docs.asc.ac.at/systems/musica.html) | [EESSI @ MUSICA](https://docs.asc.ac.at/software/eessi.html)
 
-MUSICA is currently in an open test phase.
+MUSICA is currently (Jan’26) in an open test phase.
 
 ### Belgium