GitHub Action CI: Add Go source file format check (#6090)

https://github.com/XTLS/Xray-core/pull/6057#issuecomment-4364819830

And https://github.com/XTLS/Xray-core/pull/6149#issuecomment-4546876261

app/proxyman/inbound/inbound.go

@@ -16,10 +16,10 @@ import (
 
 // Manager manages all inbound handlers.
 type Manager struct {
-	access          sync.RWMutex
+	access           sync.RWMutex
 	untaggedHandlers []inbound.Handler
-	taggedHandlers  map[string]inbound.Handler
-	running         bool
+	taggedHandlers   map[string]inbound.Handler
+	running          bool
 }
 
 // New returns a new Manager for inbound handlers.