Update CONTRIBUTING.md

Co-authored-by: Lazouich Ford <[email protected]>

Author: kjaymiller

CONTRIBUTING.md

@@ -72,7 +72,7 @@ class About(Page):
 
 ```
 
-The `@app.page` tells Render Engine that we're build a single page vs a collection of pages.
+The `@app.page` tells Render Engine that we're building a single page vs a collection of pages.
 
 The `class About(Page):` tells us about the Page object. Attributes will pass information on render engine and the jinja template that will be loaded