[ticket/16661] Remove Appveyor builds

PHPBB3-16661

README.md

@@ -37,10 +37,10 @@ phpBB's [Development Documentation](https://area51.phpbb.com/docs/dev/index.html
 
 We have unit and functional tests in order to prevent regressions. You can view the bamboo continuous integration [here](https://bamboo.phpbb.com) or check our travis builds below:
 
-Branch  | Description | Github Actions | AppVeyor
-------- | ----------- | -------------- | --------
-**master** | Latest development version | ![Tests](https://github.com/phpbb/phpbb/workflows/Tests/badge.svg?branch=master) | [![Build status](https://ci.appveyor.com/api/projects/status/8g98ybngd2f3axy1/branch/master?svg=true)](https://ci.appveyor.com/project/phpBB/phpbb/branch/master)
-**3.3.x** | Development of version 3.3.x | ![Tests](https://github.com/phpbb/phpbb/workflows/Tests/badge.svg?branch=3.3.x) | [![Build status](https://ci.appveyor.com/api/projects/status/8g98ybngd2f3axy1/branch/3.3.x?svg=true)](https://ci.appveyor.com/project/phpBB/phpbb/branch/3.3.x)
+Branch  | Description | Github Actions |
+------- | ----------- | -------------- |
+**master** | Latest development version | ![Tests](https://github.com/phpbb/phpbb/workflows/Tests/badge.svg?branch=master) |
+**3.3.x** | Development of version 3.3.x | ![Tests](https://github.com/phpbb/phpbb/workflows/Tests/badge.svg?branch=3.3.x) |
 
 ## 📜 License