Add Hiroaki Yutani to authors (#2976)

Author: yutannihilation

DESCRIPTION

@@ -13,6 +13,7 @@ Authors@R: c(
     person("Kohske", "Takahashi", role = "aut"),
     person("Claus", "Wilke", role = "aut"),
     person("Kara", "Woo", role = "aut"),
+    person("Hiroaki", "Yutani", role = "aut"),
     person("RStudio", role = c("cph"))
     )
 Depends:

GOVERNANCE.md

@@ -42,6 +42,7 @@ The core developers of ggplot2 are:
 * [Kohske Takahashi](https://github.com/kohske)
 * [Claus Wilke](https://github.com/clauswilke)
 * [Kara Woo](https://github.com/karawoo)
+* [Hiroaki Yutani](https://github.com/yutannihilation)
 
 All core developers are bound by the [code of conduct](CODE_OF_CONDUCT.md).