False positive check inserting inserting identities with l and ł values

[sduenas]

Values with polish characters l and ł are considered equal in the database giving false positives when a similar identities with these characters are inserted. For example, having the next identity in the database:

AAAAAAAA	Michał Smith	[email protected]	msmith	unknown

The call to the next command fails when the name is written with latin characters:

sortinghat add --name "Michal Smith" --email "[email protected]" --username "msmith" 
Error: unique identity 'Michal [email protected]' already exists in the registry

[sduenas]

This error is caused by the usage of utf8mb4_unicode_520_ci collation. This collation assumes these two characters are the same: see this link for more info.

We should use utf8mb4_unicode_ci while we wait for a better solution on these kind of problems.