docs(mysql): Document parseTimet=true requirement (#2699)

Author: kyleconroy

docs/tutorials/getting-started-mysql.md

@@ -99,7 +99,7 @@ import (
 func run() error {
 	ctx := context.Background()
 
-	db, err := sql.Open("mysql", "user:password@/dbname")
+	db, err := sql.Open("mysql", "user:password@/dbname?parseTime=true")
 	if err != nil {
 		return err
 	}
@@ -155,3 +155,8 @@ go build ./...
 
 To make that possible, sqlc generates readable, **idiomatic** Go code that you
 otherwise would have had to write yourself. Take a look in `tutorial/query.sql.go`.
+
+If your tables have columns with date or time types, sqlc expects these values
+to scan into `time.Time` structs. If you're using
+`github.com/go-sql-driver/mysql`, ensure that `parseTime=true` has been added to
+the connection string.