[ceph_mgr] Gather some commands in json format

[jcastill]

Capture the output of some ceph mgr commands in json
format, and add a new command to be collected.

Related: RHBZ#2116602

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Please place an 'X' inside each '[]' to confirm you adhere to our Contributor Guidelines

• Is the commit message split over multiple lines and hard-wrapped at 72 characters?
• Is the subject and message clear and concise?
• Does the subject start with [plugin_name] if submitting a plugin patch or a [section_name] if part of the core sosreport code?
• Does the commit contain a Signed-off-by: First Lastname email@example.com?
• Are any related Issues or existing PRs properly referenced via a Closes (Issue) or Resolved (PR) line?

[packit-as-a-service]

Congratulations! One of the builds has completed. 🍾

You can install the built RPMs by following these steps:

• sudo yum install -y dnf-plugins-core on RHEL 8
• sudo dnf install -y dnf-plugins-core on Fedora
• dnf copr enable packit/sosreport-sos-3179
• And now you can install the packages.

Please note that the RPMs should be used only in a testing environment.