Incorrect favicon rel attribute value - shortcut

@smulvih2 patch working fine for me
thanks

Fixed corrupted patch issue.

Rerolled the above patch #9 as it failed to apply. Please review the attached patch.

+++ b/core/modules/system/tests/src/Functional/Page/DefaultMetatagsTest.php
@@ -30,7 +30,7 @@ public function testMetaTag() {
     // Ensure that the shortcut icon is on the page.
-    $result = $this->xpath('//link[@rel = "shortcut icon"]');
+    $result = $this->xpath('//link[@rel = "icon"]');
     $this->assertCount(1, $result, 'The shortcut icon is present.');

Patch works as expected, but the test still has commented lines that refer to 'shortcut icon' instead of 'icon'. Let's update these references as well.

Rerolled the patch in #10 and addressed the changes mentioned in #11, thanks!

Adding issue credit for @idebr for #11

Can we please get a change record for this, as we're updating HTML (albeit for an error).

On that basis I think this is 9.3.x only too. Even though the value output is not valid, there may be sites depending on the broken output. We don't like to change HTML in bugfix releases.

Can we also get a release notes snippet added to the issue summary, if release managers feel this is worth listing in release notes they can use that.

Added a change notice: https://www.drupal.org/node/3220042

Added a release note snippet.

Patch looks OK to me so back to RTBC.

Committed f8dbc98 and pushed to 9.3.x. Thanks!