New Member Task: Remove Old C msg dispatcher

[DrakBoul]

Description

This task involves deleting the old C version of the msg_dispatcher because it has been replaced by its rust equivelent program called the cmd_dispatcher. To do this please delete the entire directory ex3_obc_fsw/msg_dispatcher/ so that git no longer tracks it (If done correctly you will not see the msg_dispatcher directory in your remote branch).

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