bump netlify hugo version

netlify.toml

@@ -3,6 +3,6 @@
   command = "cd exampleSite && hugo --gc --themesDir ../.."
 
 [build.environment]
-  HUGO_VERSION = "0.54.0"
+  HUGO_VERSION = "0.57.2"
   HUGO_THEME = "repo"
   HUGO_BASEURL = "https://cupper-hugo-theme.netlify.com/"