Revise require imports (#3071)

- order (external first)
- remove superfluous file extensions
- new line after imports
- deconstruct (only one time (in `check_config.js`))
- fix path (only one time (in `global-setup.js`))

js/server_functions.js

@@ -1,7 +1,7 @@
-const fetch = require("./fetch");
 const fs = require("fs");
 const path = require("path");
 const Log = require("logger");
+const fetch = require("./fetch");
 
 /**
  * Gets the config.