Update README.md openapi section for additional clarity

[MannyNe]

• The documentation section for the openapi implementation was a bit confusing to set up and where to set the patchNestJsSwagger() function in. I updated that ereadme section for more clarity for users stumbling upon that section

[BenLorantfy]

@MannyNe thanks for the contribution!

However, you don't need to call patchNestjsSwagger inside bootstrap, as shown in the example: https://github.com/BenLorantfy/nestjs-zod/blob/main/packages/example/src/main.ts#L6

[MannyNe]

Thank you for the clarification @BenLorantfy

I updated the docs again just to make it more clear for confused souls like me. I hope the update I made to the PR works. If not, you can close this PR. Thank you again, and great tool btw 😊

[BenLorantfy]

LGTM, thanks for the contribution 🙂

[MannyNe]

My pleasure 😊