DOCS:Added documentation of Keyring Feature

[anj20]

Purpose of PR?:

Fixes #2421

Does this PR introduce a breaking change?
No

Does this PR results in some Documentation changes?
Yes
Added relevant documentation updates to Test Keyring Features.

Checklist:

• Doc Changes. Fixes document an example for removing a password/key from the keyring #2421
• PR Title follows the convention of <type>: <subject>

[ReimarBauer]

see comment

[ReimarBauer]

the description is currently to generic, it should be for a dev looking into this document become faster than looking into the code.

please look into the auth module where it is used and use the default names of the configuration, e.g.
for mscolab it is defined in MSCOLAB_auth_user_name, with "mscolab"

e.g. when auth on the mscolab server is enabled you want to ask. The URL is then the service url.

keyring get MSCOLAB_AUTH_{URL} mscolab

provide the examples based on what we do and need.

look on e.g. our usage of get_password_from_keyring e.g. https://github.com/Open-MSS/MSS/blob/develop/mslib/msui/mscolab.py#L205

all the descriptions done here can be later also retrieved by perplexity.ai or similiar.