FIX (postgresql): Use UTF-8 encoding for DB connection by default

Author: RostislavDugin

backend/internal/features/databases/databases/postgresql/model.go

@@ -594,7 +594,7 @@ func buildConnectionStringForDB(p *PostgresqlDatabase, dbName string, password s
 	}
 
 	return fmt.Sprintf(
-		"host=%s port=%d user=%s password=%s dbname=%s sslmode=%s default_query_exec_mode=simple_protocol standard_conforming_strings=on",
+		"host=%s port=%d user=%s password=%s dbname=%s sslmode=%s default_query_exec_mode=simple_protocol standard_conforming_strings=on client_encoding=UTF8",
 		p.Host,
 		p.Port,
 		p.Username,