Craft 3 wont update in Laravel Valet development enviornment
I believe we were conversing via Medium yesterday on this issue.

Regarding your question, I know for a fact your PATH reference is incorrect. The path to mysqldump is never ~/.local/bin/mysqldump; mine is located at /usr/local/bin/mysqldump (I'm using MariaDB).

BUT since you said on Medium that you're using MySQL (instead of MariaDB or another database option), you should use this instead: export PATH="/usr/local/mysql/bin:$PATH".

After you add that to your .bash_profile and either source the file or quit and relaunch terminal, mysqldump should be working.