### What changes were proposed in this pull request?
User documentation for configuring SSL and authentication
### Why are the changes needed?
Document the new features.
### Does this PR introduce _any_ user-facing change?
Yes, updates documentation
### How was this patch tested?
Used `mkdocs serve` to render and validate the documentation.
Closes#2481 from mridulm/ssl-auth-documentation.
Lead-authored-by: Mridul Muralidharan <mridul@gmail.com>
Co-authored-by: Mridul Muralidharan <mridulatgmail.com>
Signed-off-by: zky.zhoukeyong <zky.zhoukeyong@alibaba-inc.com>
