Fix typo in __dirname and __filename options

[monkbroc]

node.__filename and node.__dirname accept 'node-module' as an option, not 'node_module'

Using 'node-module' works, whereas using 'node_module' gives the following error:

[webpack-cli] Invalid configuration object. Webpack has been initialized using a configuration object that does not match the API schema.
 - configuration.node.__filename should be one of these:
   false | true | "warn-mock" | "mock" | "node-module" | "eval-only"
   -> Include a polyfill for the '__filename' variable.

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• ✅ login: monkbroc / name: Julien Vanier (0dd1eed)

[alexander-akait]

Thank you

[monkbroc]

You're welcome