docs(sliceadd): ran prettier format

subjects/sliceadd/README.md

@@ -2,7 +2,7 @@
 
 ### Instructions
 
-Write a function that takes a slice of integers and an `int` as arguments, adds the `int` to the slice and returns it. 
+Write a function that takes a slice of integers and an `int` as arguments, adds the `int` to the slice and returns it.
 
 - If the slice is empty, return a slice with the new value.