Fix: Make clear, values are not empty

README.md

@@ -180,7 +180,7 @@ For examples, see [`Ergebnis\Test\Util\Test\Unit\DataProvider\NullProviderTest`]
 * `blank()` provides `string`s consisting of whitespace characters only
 * `empty()` provides an empty `string`
 * `trimmed()` provides non-empty `strings` without leading and trailing whitespace
-* `untrimmed()` provides `string`s with leading and trailing whitespace
+* `untrimmed()` provides non-empty (after trimming) `string`s with leading and trailing whitespace
 
 For examples, see [`Ergebnis\Test\Util\Test\Unit\DataProvider\StringProviderTest`](test/Unit/DataProvider/StringProviderTest.php).