fix(esx_multicharacter/server/modules/database): improve database name extraction

[RrybaN]

This fix resolves an issue where parsing the mysql_connection_string in the format user=root;password=12345;host=localhost;port=3306;database=fivem would throw an error attempt to perform arithmetic on a nil value. Additionally, i added a error log if database name is not found in the mysql_connection_string

[RrybaN]

@Mycroft-Studios any info why this was closed?

[Mycroft-Studios]

sinced since #1516 Is the correct fix.
This part of the code, was wrote by ox, so i get the feeling their extract method is alot more accuate :)

[RrybaN]

Hmm, well okay, got it.