[BUG] pro-sites seems to ignore the value of DB_COLLATE constant

Just noticed that all tables created by the pro-site plugin have "collate" value set to "utf8_unicode_ci", which is different to the value defined in my wp-config (utf8_general_ci), so it seems that the plugin ignores the value of the defined DB_COLLATE (and possibly DB_CHARSET, but I haven't tested this) constant when creating internal tables.