fix: correct variable usage for extractor in AuthorUrl class

Author: uzulla

src/Adapters/Gist/Detectors/AuthorUrl.php

@@ -17,7 +17,7 @@ public function detect(): ?UriInterface
         $owner = $api->str('owner');
 
         if ($owner !== null) {
-            return $this->extractor->getCrawler()->createUri("https://github.com/{$owner}");
+            return $extractor->getCrawler()->createUri("https://github.com/{$owner}");
         }
 
         return parent::detect();

src/Adapters/ImageShack/Detectors/AuthorUrl.php

@@ -17,7 +17,7 @@ public function detect(): ?UriInterface
         $owner = $api->str('owner', 'username');
 
         if ($owner !== null) {
-            return $this->extractor->getCrawler()->createUri("https://imageshack.com/{$owner}");
+            return $extractor->getCrawler()->createUri("https://imageshack.com/{$owner}");
         }
 
         return parent::detect();

src/Adapters/Twitter/Detectors/AuthorUrl.php

@@ -17,7 +17,7 @@ public function detect(): ?UriInterface
         $username = $api->str('includes', 'users', '0', 'username');
 
         if ($username !== null) {
-            return $this->extractor->getCrawler()->createUri("https://twitter.com/{$username}");
+            return $extractor->getCrawler()->createUri("https://twitter.com/{$username}");
         }
 
         return parent::detect();