drivers/pgsql:pgsql returning id should use quotation marks,when primary key is capital (#3638)

contrib/drivers/pgsql/pgsql_do_exec.go

@@ -9,6 +9,7 @@ package pgsql
 import (
 	"context"
 	"database/sql"
+	"fmt"
 	"strings"
 
 	"github.com/gogf/gf/v2/database/gdb"
@@ -55,7 +56,7 @@ func (d *Driver) DoExec(ctx context.Context, link gdb.Link, sql string, args ...
 	// check if it is an insert operation.
 	if !isUseCoreDoExec && pkField.Name != "" && strings.Contains(sql, "INSERT INTO") {
 		primaryKey = pkField.Name
-		sql += " RETURNING " + primaryKey
+		sql += fmt.Sprintf(` RETURNING "%s"`, primaryKey)
 	} else {
 		// use default DoExec
 		return d.Core.DoExec(ctx, link, sql, args...)