Update how_to_document_things_on_gitlab.md

documentation/how_to_document_things_on_gitlab.md

@@ -9,7 +9,7 @@ You might notice that this page is automatically rendered on our [main Gitlab
 project page](/../).
 
 Ideally, all documentation should be reachable from links on this main page.
-For documentation that is while-project encompassing, those links should go
+For documentation that is whole-project encompassing, those links should go
 on the main page itself. For documentation that is sub-topic specific (quad,
 ground station, controls), add an appropriate link on the sub topic's README.md
 page. See the Quad section for an example.