🔖 Bump version to v1.4.0

gleam.toml

@@ -1,5 +1,5 @@
 name = "gleam_community_colour"
-version = "1.3.0"
+version = "1.4.0"
 licences = ["Apache-2.0"]
 description = "Colour types, conversions, and other utilities"
 repository = { type = "github", user = "gleam-community", repo = "colour" }