Add myself to authors list

Author: oli-obk

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "tracing-tree"
 version = "0.2.5"
-authors = ["David Barsky <me@davidbarsky.com>", "Nathan Whitaker"]
+authors = ["David Barsky <me@davidbarsky.com>", "Nathan Whitaker", "Oli Scherer <tracing-tree@oli-obk.de>"]
 edition = "2018"
 license = "MIT OR Apache-2.0"
 description = "A Tracing Layer which prints a tree of spans and events."