MDL-66902 tests: Fix all incorrect namespaces

This issue just goes over all the currently incorrect
namespaces in test cases and:

1. Change the namespace to the correct one.
2. Move/rename it to correct location if needed (level 2 and down).
3. Remove not needed MOODLE_INTERNAL check when possible.
4. Remove file phpdoc when the file only has one class.
5. Make small adjustments in case the change of namespace requires it.

admin/tool/httpsreplace/tests/httpsreplace_test.php

@@ -22,8 +22,7 @@
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-namespace tool_httpsreplace\tests;
-
+namespace tool_httpsreplace;
 
 defined('MOODLE_INTERNAL') || die();