[4.5] test: update asssertion for SQLSRV ENUM

[kenjis]

Description
Follow-up #8478

1) CodeIgniter\Database\Live\SQLSRV\GetFieldDataTest::testGetFieldDataType
Failed asserting that two arrays are identical.
--- Expected
+++ Actual
@@ @@
     )
     7 => Array &8 (
         'name' => 'type_enum'
-        'type' => 'text'
-        'max_length' => 2147483647
+        'type' => 'varchar'
+        'max_length' => 5
         'nullable' => true
         'default' => null
     )

/home/runner/work/CodeIgniter4/CodeIgniter4/tests/system/Database/Live/AbstractGetFieldDataTest.php:169
/home/runner/work/CodeIgniter4/CodeIgniter4/tests/system/Database/Live/SQLSRV/GetFieldDataTest.php:229

https://github.com/codeigniter4/CodeIgniter4/actions/runs/7851204632/job/21428585497

Checklist:

• Securely signed commits
• [] Component(s) with PHPDoc blocks, only if necessary or adds value
• [] Unit testing, with >80% coverage
• [] User guide updated
• Conforms to style guide

[kenjis]

Now GA check fails in 4.5. Review this first.