DOC: Fix typo

docs/guidelines/gitlab_ci.rst

@@ -23,7 +23,7 @@ The advantages of the shared CI files are:
 
 - Pipelines are **centralised** and can (mostly) be managed in a single place
 - Changes and bug fixes must only be **applied once** (vs. multiple projects)
-- Functionaly can be **shared** used multiple times without repeating yourself (DRY)
+- Functionality can be **shared** used multiple times without repeating yourself (DRY)
 - CI files are **modular** and can depend on each other
 - Managing the CI/CD process can be done by a **single party** (i.e. CI/CD expert)
 - Developers only need to **refer files by inclusion** (no deep CI/CD knowhow required)