docs: fix link to license

Author: ttytm

README.md

@@ -137,7 +137,7 @@ or breaking changes may occur in minor(`0.<minor>.*`) versions.
 
 ## License
 
-The project is licessed under the [MIT License](https://github.com/ttytm/webview/blob/master/LICENSE).
+The project is licessed under the [MIT License](https://github.com/ttytm/webview/blob/main/LICENSE).
 
 Resources and inspiration from various works play a role when working with an contributing to
 projects. Especially in open source authors invest spare time so that others can build on their