fix: set chunkFormat: false in webpack config MONGOSH-2225 (#2460)

The mongosh CLI cannot currently handled chunked input, as the process
for building the single-executable application only uses a single file
as its input.

Author: addaleax

config/webpack.base.config.js

@@ -54,6 +54,7 @@ module.exports = {
   },
 
   output: {
+    chunkFormat: false,
     strictModuleErrorHandling: true,
     strictModuleExceptionHandling: true,
   },