Hi Ahmed, people discussed this several times, for example here:
It is always possible to add a new language or dialect to Common Voice, but be aware that this means a lot of work and you have to be able to collect many sentences under a public domain licence in that dialect.
I once wanted to add a German dialect, but it turned out to be very difficult because there is no standardized form and not enough sentences available. If your variation of Arabic does have a separate version of Wikipedia your chances are good that you will be able to start it.
EDIT: looks like Egyptian Arabic is the only Arabic dialect that has its own Wikipedia: مصريين - ويكيبيديا