Revert "doc: add more enum examples (#7510)"

This reverts commit f66569ee1a.

doc/docs.md

@@ -1781,25 +1781,12 @@ mut color := Color.red
 // V knows that `color` is a `Color`. No need to use `color = Color.green` here.
 color = .green
 println(color) // "green"
-// enum starts by default at 0
-println(color == 1) // true
 
 match color {
     .red { println('the color was red') }
     .green { println('the color was green') }
     .blue { println('the color was blue') }
 }
-
-
-// It's possible to override enum values
-enum Size {
-	small = -1
-	medium = 0
-	large = 1
-}
-
-mut s := Size.small
-println(s == -1) // true
 ```
 
 Enum match must be exhaustive or have an `else` branch.