Remove broken Travis-CI badge

In 027713c ("Update CI to GitHub Actions", 2024-11-25) we removed
the .travis.yml file, time to clean up the read-me from the badge.

Author: ktomk

README.md

@@ -1,5 +1,4 @@
 [![Net_URL2 on Packagist](https://poser.pugx.org/pear/net_url2/v/stable.png)][pear/net_url2]
-[![Build Status](https://travis-ci.org/pear/Net_URL2.png)][Travis CI]
 [![Scrutinizer Quality Score](https://scrutinizer-ci.com/g/pear/Net_URL2/badges/quality-score.png?s=23b0d3f0ed58ee865317c500ee2cbe94517438ec)](https://scrutinizer-ci.com/g/pear/Net_URL2/)
 [![Code Coverage](https://scrutinizer-ci.com/g/pear/Net_URL2/badges/coverage.png?s=44d3682d7cdef471570d80dd8a7290a1e23fdfee)](https://scrutinizer-ci.com/g/pear/Net_URL2/)
 
@@ -18,7 +17,6 @@ On Packagist as [pear/net_url2].
 [Pear SVN]: https://svn.php.net/repository/pear/packages/Net_URL2
 [PEAR bug tracker]: https://pear.php.net/bugs/search.php?cmd=display&package_name%5B%5D=Net_URL2
 [pear/net_url2]: https://packagist.org/packages/pear/net_url2
-[Travis CI]: https://travis-ci.org/pear/Net_URL2
 
 ## Testing, Packaging and Installing (Pear)