refactor: do not use $this->binds when updateBatch()

To reduce memory consumption.

Author: kenjis

system/Database/BaseBuilder.php

@@ -2076,9 +2076,8 @@ public function setUpdateBatch($key, string $index = '', ?bool $escape = null)
                     $indexSet = true;
                 }
 
-                $bind = $this->setBind($k2, $v2, $escape);
-
-                $clean[$this->db->protectIdentifiers($k2, false)] = ":{$bind}:";
+                $clean[$this->db->protectIdentifiers($k2, false)]
+                    = $escape ? $this->db->escape($v2) : $v2;
             }
 
             if ($indexSet === false) {

tests/system/Database/Builder/UpdateTest.php

@@ -208,19 +208,6 @@ public function testUpdateBatch()
 
         $space = ' ';
 
-        $expected = <<<EOF
-            UPDATE "jobs" SET "name" = CASE{$space}
-            WHEN "id" = :id: THEN :name:
-            WHEN "id" = :id.1: THEN :name.1:
-            ELSE "name" END, "description" = CASE{$space}
-            WHEN "id" = :id: THEN :description:
-            WHEN "id" = :id.1: THEN :description.1:
-            ELSE "description" END
-            WHERE "id" IN(:id:,:id.1:)
-            EOF;
-
-        $this->assertSame($expected, $query->getOriginalQuery());
-
         $expected = <<<EOF
             UPDATE "jobs" SET "name" = CASE{$space}
             WHEN "id" = 2 THEN 'Comedian'
@@ -261,19 +248,6 @@ public function testSetUpdateBatchWithoutEscape()
 
         $space = ' ';
 
-        $expected = <<<EOF
-            UPDATE "jobs" SET "name" = CASE{$space}
-            WHEN "id" = :id: THEN :name:
-            WHEN "id" = :id.1: THEN :name.1:
-            ELSE "name" END, "description" = CASE{$space}
-            WHEN "id" = :id: THEN :description:
-            WHEN "id" = :id.1: THEN :description.1:
-            ELSE "description" END
-            WHERE "id" IN(:id:,:id.1:)
-            EOF;
-
-        $this->assertSame($expected, $query->getOriginalQuery());
-
         $expected = <<<EOF
             UPDATE "jobs" SET "name" = CASE{$space}
             WHEN "id" = 2 THEN SUBSTRING(name, 1)