docs(readme): add build and release badges

README.md

@@ -1,8 +1,10 @@
-[![Build Status][badge-travis-image]][badge-travis-url]
+![[Build Status][gha-workflow-badge]][gha-workflow-url] ![[Latest release][gha-latest-release]][gha-releases-url]
 
 # Kong Plugin Development Kit - Go edition
 
 Docs: https://pkg.go.dev/github.com/Kong/go-pdk.
 
-[badge-travis-url]: https://travis-ci.com/Kong/go-pdk/branches
-[badge-travis-image]: https://travis-ci.com/Kong/go-pdk.svg?branch=master
+[gha-workflow-badge]: https://github.com/Kong/go-pdk/actions/workflows/test.yml/badge.svg
+[gha-workflow-url]: https://github.com/Kong/go-pdk/actions/workflows/test.yml
+[gha-latest-release]: https://img.shields.io/github/v/release/Kong/go-pdk.svg
+[gha-releases-url]: https://github.com/Kong/go-pdk/releases