mysql Ver 8.0.20-0ubuntu0.20.04.1 for Linux on x86_64 ((Ubuntu))
Doing at the mysql> prompt:
update user set authentication_string=password('my-password-here'), plugin='mysql_native_password' where user='root';
Gives an error:
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '('my-password-here'), plugin='mysql_native_password' where user='root at line 1
So instead I did:
ALTER USER 'root'@'localhost' IDENTIFIED BY 'my-password-here';
Which seems to work ok with:
Query OK, 0 rows affected (0.01 sec)