failed: could not find driver
For anyone from the future, this worked for me utilizing Ubuntu 16.0.4 with PHP7.2:

Try this command:

sudo phpenmod pdo_mysql


If it says it cant find the package, install this:

sudo apt-get install php7.2-mysql


Check your active php.ini file for this line(my active .ini was located n /etc/php/7.2/apache2/php.ini):

;extension=pdo_mysql


If it has a semicolon before it, remove it, and then save. For good measure, run this again:

sudo phpenmod pdo_mysql


Restart apache. Good day.