WhiteSpace/FunctionSpacing: minor tweak

The parent `process()` method is a `void` method, so this should be too.

Yoast/Sniffs/WhiteSpace/FunctionSpacingSniff.php

@@ -51,14 +51,14 @@ final class FunctionSpacingSniff extends Squiz_FunctionSpacingSniff {
 	 * @param File $phpcsFile The file being scanned.
 	 * @param int  $stackPtr  The position of the current token in the stack passed in $tokens.
 	 *
-	 * @return void|int Optionally returns stack pointer to skip to.
+	 * @return void
 	 */
 	public function process( File $phpcsFile, $stackPtr ) {
 		// Check that the function is nested in an OO structure (class, trait, interface, enum).
 		if ( Conditions::hasCondition( $phpcsFile, $stackPtr, Tokens::$ooScopeTokens ) === false ) {
 			return;
 		}
 
-		return parent::process( $phpcsFile, $stackPtr );
+		parent::process( $phpcsFile, $stackPtr );
 	}
 }