Fix doc and add child spec

src/gleam/otp/actor.gleam

@@ -1,7 +1,7 @@
 //// This module provides the _Actor_ abstraction, one of the most common
 //// building blocks of Gleam OTP programs.
 //// 
-//// An Actor is a process like any other BEAM process and can be be used to hold
+//// An Actor is a process like any other BEAM process and can be used to hold
 //// state, execute code, and communicate with other processes by sending and
 //// receiving messages. The advantage of using the actor abstraction over a bare
 //// process is that it provides a single interface for commonly needed

src/gleam/otp/static_supervisor.gleam

@@ -286,6 +286,7 @@ fn convert_child(child: ChildBuilder) -> Dict(Atom, Dynamic) {
   |> property("id", child.id)
   |> property("start", mfa)
   |> property("restart", child.restart)
+  |> property("significant", child.significant)
   |> property("type", type_)
   |> property("shutdown", shutdown)
 }