Fix up deprecation removal changelog headers (#75848)

changelogs/fragments/75823-cli-remove-deprecated-verbosity-before-sub-cmd.yml

@@ -1,2 +1,2 @@
-bugfixes:
+removed_features:
   - cli - remove deprecated ability to set verbosity before the sub-command (https://github.com/ansible/ansible/issues/75823)

changelogs/fragments/75824-copy-remove-deprecated-thirsty-alias.yml

@@ -1,2 +1,2 @@
-bugfixes:
+removed_features:
   - copy - remove deprecated ``thirsty`` alias (https://github.com/ansible/ansible/issues/75824)

changelogs/fragments/75825-75826-get_url-uri-remove-deprecated-thirsty-alias.yml

@@ -1,2 +1,2 @@
-bugfixes:
+removed_features:
   - url_argument_spec - remove deprecated ``thirsty`` alias for ``get_url`` and ``uri`` modules (https://github.com/ansible/ansible/issues/75825, https://github.com/ansible/ansible/issues/75826)

changelogs/fragments/75828-remove-deprecated-set_available_variables.yml

@@ -1,2 +1,2 @@
-bugfixes:
+removed_features:
   - Remove deprecated ``Templar.set_available_variables()`` method (https://github.com/ansible/ansible/issues/75828)