working on small memory SBC

Describe the bug

On small memory SingleBoardComputer the services "jvb" and "jicofo" don't want to start.

Context

Hardware: odroid hc1 armhf(v7) 2Gb RAM
YunoHost version: 4.3.6.2
I have access to my server: Through SSH | through the webadmin
Are you in a special context or did you perform some particular tweaking on your YunoHost instance?: yes
- If yes, please explain: inside lxc container
Using, or trying to install package version/branch: master
If upgrading, current package version: NA

Steps to reproduce

install
verify services jitsi-cofo and jitsi-videobridge not starting with log error indicates that VM memory alocation 3000 mb failed.

Expected behavior

ability to run jitsi on small memory platform as most yunohost users will not use it as public server. reduce the VM memory allocation.

as indicates in https://jitsi.org/jitsi-videobridge-performance-evaluation/ memory used at maximum were 1500mb with 1056 participant(1056 video streams+1056 audio streams) we could calculate a usage of 1,5 mb per user. maybe it should be possible to ask the admin for how many people he want to use for the service and allocate VM memory in relation. it exist 2 shell variable to set before starting the services. (for 70 mega set value to 70m) VIDEOBRIDGE_MAX_MEMORY (tested and set in /var/www/jitsi/jitsi-videobridge/jvb.sh) JICOFO_MAX_MEMORY (tested and set in /var/www/jitsi/jitsi-jicofo/jicofo.sh)

the reason why i don't do a PR is that i don't know how the variables should be set from the yunohost scripts

YunoHost-Apps / jitsi_ynh