sudo mysql -u root -p
FLUSH PRIVILEGES;
ALTER USER 'root'@'localhost' IDENTIFIED BY ''

Query OK, 0 rows affected (0.00 sec)

!includedir /etc/mysql/conf.d/
!includedir /etc/mysql/mysql.conf.d/

[mysqld]
socket=/var/run/mysqld/mysqld.sock

[client]
user=root
password=""

[mysql]
user=root
password=""

[mysqldump]
user=root
password=""

[mysqldiff]
user=root
password=""

sudo mysqld --skip-grant-tables &

mysql -u root -p
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/run/mysqld/mysqld.sock' (2)