fix: remove hard code for cache.

examples/auto-tls/main.go

@@ -2,16 +2,19 @@ package main
 
 import (
 	"github.com/gin-gonic/gin"
+	"golang.org/x/crypto/acme/autocert"
 )
 
 func main() {
 	r := gin.Default()
 
+	gin.AutoTLSManager.Cache = autocert.DirCache("/var/www/.cache")
+
 	// Ping handler
 	r.GET("/ping", func(c *gin.Context) {
 		c.String(200, "pong")
 	})
 
 	// Listen and Server in 0.0.0.0:443
-	r.RunAutoTLS(":443", "/var/www/.cache", "example.com")
+	r.RunAutoTLS("example.com")
 }