unsupported media type for "application/json; charset=utf-8"

Hi, my company has a rule that we mandatory set Content-Type: application.json; charset=utf-8 to all the request/response header. (I know the charset=utf-8 is probably redundant for json though.) Since OpenAPI Validator drop charactors of Content-Type after the charactor of ; as below, our OpenAPI Validator cannot find the appropriate request body schema and respond unsupported media type application/json.

https://github.com/cdimascio/express-openapi-validator/blob/04a84e513ab253f7d7e655c53bdac7978ba43093/src/middlewares/util.ts#L6-L17

Sample api spec is described as below. Due to the issue above, requests which has Content-Type: application.json; charset=utf-8 cannot be associated with the schema $ref: '#/components/schemas/user'.

paths:
  /user/:userId:
    post:
# --- skip ---
      requestBody:
        content:
          application/json; charset=utf-8:
            schema:
              $ref: '#/components/schemas/user'
# --- skip ---

I think we should use original raw value of Content-Type in request header to find appropriate schema.

https://github.com/cdimascio/express-openapi-validator/blob/04a84e513ab253f7d7e655c53bdac7978ba43093/src/middlewares/openapi.request.validator.ts#L196

If you feel okay with my suggestion, let me create PR.

[cdimascio]

fix available in v2.15.1

[cdimascio]

@mk811 how are you making out? If u have any questions or want to discuss more freely, feel free to join us on gitter. https://gitter.im/cdimascio-oss/community