Adds new properties to the dashboard definition to customize format

Background

As part of our dogfooding effort, we found users want more flexibility to select the format of their values: #201999 (closed)

!25687 (merged) defines formats that now could become available to users.

What does this MR do?

This MR adds support for defining formats (units) in dashboards .yml.

Three new properties are added y_axis.name, y_axis.format, y_axis.precision to a panel definition:

- panels:
  - title: 
    # ...
    y_axis:
      name: "Axis Name" # NEW
      format: "bytes" # NEW, one of SUPPORTED_FORMATS
      precision: 2 # NEW, fractional decimals (0.00), defaults to 2

Also y_label gets deprecated in favor of y_axis.name.

For example, in common_metrics.yml, we modify a panel like this:

Before: - title: "Memory Usage (Total)" weight: 4 type: "area-chart" y_label: "Total Memory Used (GB)" # TO BE DEPRECATED metrics: - id: system_metrics_kubernetes_container_memory_total query_range: 'avg(....) by (job)) without (job) /1024/1024/1024' label: Total (GB) unit: GB

After: - title: "Memory Usage (Total)" weight: 4 type: "area-chart" y_axis: # NEW PROPERTY y_axis name: "Total Memory Used" # NEW PROPERTY format: "bytes" # NEW PROPERTY, one of formats (*) metrics: - id: system_metrics_kubernetes_container_memory_total query_range: 'avg(....) by (job)) without (job)' # `/1024/1024/1024` IS REMOVED** label: Total

• * See SUPPORTED_FORMATS https://gitlab.com/gitlab-org/gitlab/-/blob/master/app/assets/javascripts/lib/utils/unit_format/index.js#L8
• ** Operations like /1000/1000/1000 to adjust units scales can be removed in favor of bytes.

Screenshots

before	after

• GB units are removed in favor of being calculated dynamically
• There is more space to display the axis name (left)
• Tooltip formatting is taken from axis (but not the precision)

What does this MR does not do?

Change our current dashboards!

This MR is backwards compatible, documentation and other changes will be addressed at: #208258 (closed)

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required) -> #208258 (closed)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #201999 (closed)