fileUploader doesn't fully replace multerOpts

[JacobLey]

Hello,

I think I've run into an issue regarding the change from multerOpts to fileUploader.

https://github.com/cdimascio/express-openapi-validator/pull/205/files
With the recent version 3.6.3 when I provide multerOpts (unchanged usage, but according to README it is acceptable for now) files get cached locally instead of forwarded onto the provided storage (I was providing a storage attribute, but thats getting farther into multer's settings).

I tried changing the variable name to fileUploader but still behavior is not desired.

Looking through the code, its looks like my issue comes from this line: https://github.com/cdimascio/express-openapi-validator/blob/master/src/index.ts#L153

Essentially I think multerOpts should be replaced with fileUploader to match the rest of the logic: https://github.com/cdimascio/express-openapi-validator/blob/master/src/index.ts#L153

Does that make sense?
Opened a PR to help highlight the issue and hopefully fix: #221

[cdimascio]

thanks for the ticket and the fix. merged in 3.6.6