Merge branch 'docs-change-key-capitalization' into 'master'

Docs: change capitalization of "Key" to "key"

See merge request gitlab-org/gitlab!41469

doc/api/users.md

@@ -776,7 +776,7 @@ POST /user/keys
 
 Parameters:
 
-- `title` (required) - new SSH Key's title
+- `title` (required) - new SSH key's title
 - `key` (required) - new SSH key
 - `expires_at` (optional) - The expiration date of the SSH key in ISO 8601 format (`YYYY-MM-DDTHH:MM:SSZ`)
 
@@ -815,7 +815,7 @@ POST /users/:id/keys
 Parameters:
 
 - `id` (required) - ID of specified user
-- `title` (required) - new SSH Key's title
+- `title` (required) - new SSH key's title
 - `key` (required) - new SSH key
 - `expires_at` (optional) - The expiration date of the SSH key in ISO 8601 format (`YYYY-MM-DDTHH:MM:SSZ`)