Add remark about SSL path for Docker daemon behind an HTTPS_PROXY

[k33g]

Description

In the documentation related to Running a Docker daemon behind an HTTPS_PROXY, it's written:

2. Ask your network admin for the proxy's CA certificate and append them to
   `/etc/pki/tls/certs/ca-bundle.crt`

Perhaps, we should add a remark explaining that this path is for the RH family distributions (because it can be different with other Linux distributions. e.g. for Debian and Ubuntu it's /etc/ssl/certs).

[Pushkarmondal]

Hey @k33g can I work on this issue?

[k33g]

Hello @Pushkarmondal, I'm not part of the moderators of this repository