[feature]split user and password from uri

[naughtyGitCat]

Is your feature request related to a problem? Please describe.
expose monitoring mongo instance URI will be helpful when handling problems, but exposing user pass is insecure

Describe the solution you'd like
user and pass supply in env variables

Describe alternatives you've considered
use --remark or --note to add extra info, such as --note=IP:PORT

[denisok]

similar request is in #380 . As a secure alternative so far you can use tls connection with --web.config which is Prometheus TLS config file

[denisok]

hm. I mixed up the things, --web.config is the parameter for exporter itself. It will not help with connection to mongo. So yeah, concern is quite critical we need to address it.

[denisok]

to make it clear --web-config is for exporter itself, but you still use tls in a connection URI: tls=truetlsCertificateKeyFile=Server.pem&tlsCAFile=ca.pem in connection string instead of password.

[naughtyGitCat]

thanks, TLS may be another way to secure the exporter, and seems a little inconvenient to me. we want to expose the monitoring DB instance URL