exampleSite: Fix project link

exampleSite/content/publication/clothing-search.md

@@ -36,7 +36,7 @@ selected = true
 #   Simply enter your project's filename without extension.
 #   E.g. `projects = ["deep-learning"]` references `content/project/deep-learning.md`.
 #   Otherwise, set `projects = []`.
-projects = ["example-external-project.md"]
+projects = ["example-external-project"]
 
 # Tags (optional).
 #   Set `tags = []` for no tags, or use the form `tags = ["A Tag", "Another Tag"]` for one or more tags.