Graph cluster wide where applicable

[shtripat]

Community Contribution License

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under the terms of the Apache 2 license.
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contributions to the project maintainers under the Apache 2 license.

Description

Graph the maximum value reported across nodes at cluster level for applicable scenarios.

Motivation and Context

As commented here, some of these graphs make more sense at cluster level, so take maximum value reported across nodes and render.

How to test this PR?

Load the dashboard in grafana and visualize.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Optimization (provides speedup with no functional changes)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (If yes, please add commit-id or PR # here)
• Unit tests added/updated
• Internal documentation updated
• Create a documentation update request here