* Update aws.mdx
Was looking how to give the vault agent with AWS auth-auth the same nonce, but saw it wasn't documented. Dove through the code, found https://github.com/hashicorp/vault/blob/master/command/agent/auth/aws/aws.go#L139 and https://github.com/hashicorp/vault/blob/master/command/agent/auth/aws/aws.go#L215
(tried to call out the importance and point to docs, know setting `nonce` poorly could be very bad!)
* add line breaks
* Apply suggestions from code review
Co-authored-by: Loann Le <84412881+taoism4504@users.noreply.github.com>
Co-authored-by: hghaf099 <83242695+hghaf099@users.noreply.github.com>
Co-authored-by: Loann Le <84412881+taoism4504@users.noreply.github.com>
