Fix outdated comment

src/Composer/Installer.php

@@ -968,7 +968,7 @@ class Installer
 
                 // update the dist and source URLs
                 $package->setSourceUrl($newPackage->getSourceUrl());
-                // only update dist url for github dists as they use a combination of dist url + dist reference to install
+                // only update dist url for github/bitbucket dists as they use a combination of dist url + dist reference to install
                 // but for other urls this is ambiguous and could result in bad outcomes
                 if (preg_match('{^https?://(?:(?:www\.)?bitbucket\.org|(api\.)?github\.com)/}', $newPackage->getDistUrl())) {
                     $package->setDistUrl($newPackage->getDistUrl());