Move search relevance card tests to search plugin

[yubonluo]

Description

Move search relevance card to search plugin

yarn cypress run --spec cypress/integration/core-opensearch-dashboards/opensearch-dashboards/workspace-plugin/mds_workspace_search_overviews.spec.js

  Search workspace overview
    ✓ Set up search cards display correctly (19982ms)
    ✓ Different search techniques section display correctly (5940ms)

  2 passing (29s)

yarn cypress run --spec cypress/integration/plugins/search-relevance-dashboards/2_search_card.spec.js  

 Search card
    ✓ Configure and evaluate search cards should display correctly (20396ms)


  1 passing (23s)

Issues Resolved

N/A

Check List

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