chore: remove codeskyblue/go-sh

It has been replaced with alexellis/go-execute.

plugins/common/subprocess.go

@@ -3,23 +3,8 @@ package common
 import (
 	"path/filepath"
 	"strings"
-
-	"github.com/codeskyblue/go-sh"
 )
 
-// PlugnTriggerSetup sets up a plugn trigger call
-//
-// Deprecated: use CallPlugnTrigger with Stdin instead
-func PlugnTriggerSetup(triggerName string, args ...string) *sh.Session {
-	shellArgs := make([]interface{}, len(args)+2)
-	shellArgs[0] = "trigger"
-	shellArgs[1] = triggerName
-	for i, arg := range args {
-		shellArgs[i+2] = arg
-	}
-	return sh.Command("plugn", shellArgs...)
-}
-
 // PlugnTriggerExists returns whether a plugin trigger exists (ignoring the existence of any within the 20_events plugin)
 func PlugnTriggerExists(triggerName string) bool {
 	pluginPath := MustGetEnv("PLUGIN_PATH")