doc: fix documentation examples (#17804)

doc/docs.md

@@ -4886,7 +4886,6 @@ Documentation for each function/type/const must be placed right before the decla
 
 ```v
 // clearall clears all bits in the array
-
 fn clearall() {
 }
 ```
@@ -4899,7 +4898,6 @@ span to the documented function using single line comments:
 ```v
 // copy_all recursively copies all elements of the array by their value,
 // if `dupes` is false all duplicate values are eliminated in the process.
-
 fn copy_all(dupes bool) {
 	// ...
 }