Don't use localhost in Tests_Image_Header tests

[ocean90]

Tests_Image_Header::test_create_attachment_object() and Tests_Image_Header::test_insert_cropped_attachment() are passing http://localhost/foo-cropped.png to Custom_Image_Header::create_attachment_object(). This method is using getimagesize() for the URL. I'm not sure if this a config issue but it seems like the timeout is pretty high so the tests are taking a minute to complete.

Output of PHPunit:

1) Tests_Image_Header::test_create_attachment_object
ImagickException: getimagesize(http://localhost/foo-cropped.png): failed to open stream: Connection refused

src/wp-admin/custom-header.php:1160
tests/phpunit/tests/image/header.php:116

2) Tests_Image_Header::test_insert_cropped_attachment
ImagickException: getimagesize(http://localhost/foo-cropped.png): failed to open stream: Connection refused

src/wp-admin/custom-header.php:1160
tests/phpunit/tests/image/header.php:132

[celloexpressions]

+1, can someone make a patch? This was presumably introduced in 3.9.

[stevenlinx]

sry., what URLs do you propose to use instead?

[ocean90]

Duplicate of #41216.