Update the documentation links

Updates the example and dependency links in the documentation, to use URLs that
are valid within the monorepo.

Signed-off-by: Gergely Nagy <algernon@keyboard.io>

doc/plugin/LEDEffect-SolidColor.md

@@ -23,7 +23,7 @@ void setup() {
 
 ## Dependencies
 
-* [Kaleidoscope-LEDControl](https://github.com/keyboardio/Kaleidoscope-LEDControl)
+* [Kaleidoscope-LEDControl](LEDControl.md)
 
 ## Upgrading