refactor: rename controller to Controller

[paulbalandan]

Description
Last errors for class.nameCase

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

[samsonasik]

it seems cause test error:

1) CodeIgniter\Router\RouteCollectionTest::testAddRecognizesCustomNamespaces
Failed asserting that two arrays are identical.
--- Expected
+++ Actual
@@ @@
 Array &0 [
-    'home' => '\CodeIgniter\Controller',
+    'home' => '\CodeIgniter\controller',
 ]

[michalsn]

Always sand in the eyes 😢

[samsonasik]

Thank you @paulbalandan