Add zulip stream to readme

Author: arora-aman

README.md

@@ -7,5 +7,6 @@ See also:
 * [RFC 2229]
 * [Rust tracking issue, rust-lang/rust#53488](https://github.com/rust-lang/rust/issues/53488)
 * [Plan](https://hackmd.io/HNEgTkPlTuy6cb9v29rzIQ)
+* [Zulip Stream](https://rust-lang.zulipchat.com/#narrow/stream/189812-t-compiler.2Fwg-rfc-2229)
 
 [RFC 2229]: https://github.com/rust-lang/rfcs/blob/master/text/2229-capture-disjoint-fields.md