fix: wrong comment sys

Author: xieyuen

config/_default/params.toml

@@ -51,7 +51,7 @@ SortBy              = "default"
 ## Comments
 [comments]
     enabled  = true
-    provider = "disqus"
+    provider = "giscus"
 
     # See all the available configurations at https://github.com/CaiJimmy/hugo-theme-stack/blob/master/config/_default/params.toml
     # Copy the configurations you need from there and paste it here.