Replace signal USR1 with WINCH

modules/prompt/functions/prompt_sorin_setup

@@ -67,7 +67,7 @@ function prompt_sorin_precmd_async {
   fi
 
   # Signal completion to parent process.
-  kill -USR1 $$
+  kill -WINCH $$
 }
 
 function prompt_sorin_precmd {
@@ -86,7 +86,7 @@ function prompt_sorin_precmd {
   fi
 
   # Compute slow commands in the background.
-  trap prompt_sorin_git_info USR1
+  trap prompt_sorin_git_info WINCH
   prompt_sorin_precmd_async &!
   _prompt_sorin_precmd_async_pid=$!
 }