Fix pdoodbc_002.phpt to not try to load PDO_odbc (GH-16096)

In the `--EXTENSIONS--` section, names of extension are handled case-
sensitively.

Author: cmb69

ext/pdo_odbc/tests/pdoodbc_002.phpt

@@ -1,7 +1,7 @@
 --TEST--
 PDO_mysql connect through PDO::connect
 --EXTENSIONS--
-PDO_odbc
+pdo_odbc
 --SKIPIF--
 <?php
 require 'ext/pdo/tests/pdo_test.inc';