[Backport 2.X] MDS support in Integrations for observability plugin (#2051)

[sumukhswamy]

Manual backport for https://github.com/opensearch-project/dashboards-observability/pull/2051

• Support for MDS in integrations

• added changes for mds support in integrations

• fixed case for Local cluster

• addressed comments for undefined variables

• updated snapshots

• changed the refrences object in integrations instance

• addressed pr comments

• updated snapshots

• [Page Header] New page header for metrics (#2050)

• Move the save button to the header control bar

• Update snapshots

• Fix the save button and correct its size + position

• Fix the date picker location

• Rename the navigation in coreRef and switch to use compressed date picker

• Fix the popover

• Rename the button

• Update to latest mockup

• Update snapshots

• Fix the ui issues

• Dummy metrics

• Remove dummy

• update snapshots

• minor changes to match mocks

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• Updated event analytics and integrations components

• updated tests and conditions

• updated snapshots

• updated snapshots

• updated snapshots

• updated the remote and local for snapshots

• updated snapshots

• updated snapshots again

• updated snapshots

• updated snapshots

• updated missing import

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Description

[Describe what this change achieves]

Issues Resolved

[List any issues this PR will resolve]

Check List

• [ ] New functionality includes testing.
  • [ ] All tests pass, including unit test, integration test and doctest
• [ ] New functionality has been documented.
  • [ ] New functionality has javadoc added
  • [ ] New functionality has user manual doc added
• [ ] Commits are signed per the DCO using --signoff

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