fix: Add loading state for MetricsViewTimerange query

[AdityaHegde]

closes #6646

We make a call to MetricsViewTimerange API in loader functions. The problem with this is we cannot add a loader state without moving the fetching out of it. While we can handle navigation from non-dashboard to dashboard page a direct visit of a dashboard doesnt start rendering until all layout and page loader functions are run.

Converting the data to promises and awaiting in page component. This also means we dont have to set runtime in layout page.

Checklist:

• Covered by tests
• Ran it and it works as intended
• Reviewed the diff before requesting a review
• Checked for unhandled edge cases
• Linked the issues it closes
• Checked if the docs need to be updated
• Intend to cherry-pick into the release branch
• I'm proud of this work!