docs: fix link typo in 02-conventions.mdx (#3214)

Closes #3213

## Changes:

- add preceding `/` to Resources link

site/docs/02-fundamentals/02-conventions.mdx

@@ -9,7 +9,7 @@ There are a few things that Excalibur does that are good to know before you star
 
 1. Excalibur uses a theater metaphor, for example: [[Scene|Scenes]], [[Actor|Actors]], and [Actions](/docs/actions).
 
-2. Excalibur uses [Resources](docs/category/resources) to load external files like [images](/docs/ImageSource) and [sounds](/docs/Sound). They can also be used to load other things like data or config.
+2. Excalibur uses [Resources](/docs/category/resources) to load external files like [images](/docs/ImageSource) and [sounds](/docs/Sound). They can also be used to load other things like data or config.
 
 2. The negative y direction is up, and the positive y direction is down.