Enable users to export diagnostics data via Kyma CLI

[kwiatekus]

Description

Provide a kyma CLI command that would output diagnostic data, such as:

• Non-ready statuses of Kyma Module CRs (including conditions)
• resource saturation of the nodes
• k8s error/warning events with kyma-system namespace
• cluster metadata (i.e SAP BTP global account, subaccount, provider (azure, aws, etc..), api server url)

For example:

kyma alpha diagnose (--output {filepath}) (--fromat {yaml|json})

Module providers can further extend the command by adding sub-commands for their modules:
I.e kyma alpha diagnose keda could output keda specific metrics
I.e kyma alpha keda docs could open url in browser

Reasons

When users report defects we asked them to provide kyma installation details in order to better understand the problem. This feature will provide a standardised way of providing diagnostic data, which will help us better support the users, but also may expose some symptoms to the user himself.

[kwiatekus]

As we discussed:

• please extend the warning events to all namespaces (the requirements adjusted)
• please rename the moduleCustomResourceStates to kymaModulesErrors