readme: drop forum for discussions (#449)

README.md

@@ -96,7 +96,7 @@ checkout the official documentation:
 - [![GoDoc](https://godoc.org/github.com/getsentry/sentry-go?status.svg)](https://godoc.org/github.com/getsentry/sentry-go)
 - [![go.dev](https://img.shields.io/badge/go.dev-pkg-007d9c.svg?style=flat)](https://pkg.go.dev/github.com/getsentry/sentry-go)
 - [![Documentation](https://img.shields.io/badge/documentation-sentry.io-green.svg)](https://docs.sentry.io/platforms/go/)
-- [![Forum](https://img.shields.io/badge/forum-sentry-green.svg)](https://forum.sentry.io/c/sdks)
+- [![Discussions](https://img.shields.io/github/discussions/getsentry/sentry-go.svg)](https://github.com/getsentry/sentry-go/discussions)
 - [![Discord](https://img.shields.io/discord/621778831602221064)](https://discord.gg/Ww9hbqr)
 - [![Stack Overflow](https://img.shields.io/badge/stack%20overflow-sentry-green.svg)](http://stackoverflow.com/questions/tagged/sentry)
 - [![Twitter Follow](https://img.shields.io/twitter/follow/getsentry?label=getsentry&style=social)](https://twitter.com/intent/follow?screen_name=getsentry)