Update Misty's GitHub handle

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
diff --git a/MAINTAINERS b/MAINTAINERS
index b3dfd49..d81caba 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -364,7 +364,7 @@
 	[people.misty]
 	Name = "Misty Stanley-Jones"
 	Email = "misty@docker.com"
-	GitHub = "mstanleyjones"
+	GitHub = "mistyhacks"
 
 	[people.mlaventure]
 	Name = "Kenfe-Mickaël Laventure"