replace my twitter handle with active one (rust-gamedev#36)

Author: fu5ha

_posts/2019-11-07-newsletter-003.md

@@ -635,7 +635,7 @@ _Discussions:
 [/r/rust](https://reddit.com/r/rust/comments/dpknd1/ultraviolet_a_crate_to_do_lots_of_linear_algebra)_
 
 [ultraviolet]: https://github.com/termhn/ultraviolet
-[@termhn]: https://twitter.com/termhn
+[@fu5ha]: https://twitter.com/fu5ha
 [SIMD]: https://en.wikipedia.org/wiki/SIMD
 [aos_soa]: https://en.wikipedia.org/wiki/AoS_and_SoA