[ckan#8596] Don't encode binary font files when building frontend

There was a change in gulp 5 that defaulted the stream encoding to
UTF8. To preserve binary files like fonts you need to
pass `{encoding: false}`

Reference:

gulpjs/gulp#2797

Author: amercader

gulpfile.js

@@ -69,7 +69,7 @@ const fontAwesomeCss = () =>
   );
 
 const fontAwesomeFonts = () =>
-  src(__dirname + "/node_modules/@fortawesome/fontawesome-free/webfonts/*").pipe(
+  src(__dirname + "/node_modules/@fortawesome/fontawesome-free/webfonts/*", {"encoding": false}).pipe(
     dest(__dirname + "/ckan/public/base/vendor/fontawesome-free/webfonts")
   );