[CLEANUP] Clean extra whitespace in css selector

src/Property/Selector.php

@@ -9,6 +9,7 @@
 use Sabberworm\CSS\Renderable;
 
 use function Safe\preg_match;
+use function Safe\preg_replace;
 
 /**
  * Class representing a single CSS selector. Selectors have to be split by the comma prior to being passed into this
@@ -74,7 +75,7 @@ public function getSelector(): string
 
     public function setSelector(string $selector): void
     {
-        $this->selector = \trim($selector);
+        $this->selector = preg_replace('/\s{1,}/', ' ', \trim($selector));
     }
 
     /**

tests/ParserTest.php

@@ -771,7 +771,7 @@ public function selectorIgnoresInFile(): void
         $document = self::parsedStructureForFile('selector-ignores', Settings::create()->withMultibyteSupport(true));
         $expected = '.some[selectors-may=\'contain-a-{\'] {}'
             . "\n"
-            . '.this-selector  .valid {width: 100px;}'
+            . '.this-selector .valid {width: 100px;}'
             . "\n"
             . '@media only screen and (min-width: 200px) {.test {prop: val;}}';
         self::assertSame($expected, $document->render());