Convert QualityMetrics components from class components to functional components

[Parship999]

Which problem is this PR solving?

• Resolves part of [Feature]: Refactor class components to functional components #2610

Description of the changes

• Converted the following components to functional components:
  • BannerText.tsx
  • CountCard.tsx
  • MetricCard.tsx
  • ScoreCard.tsx
• Added React.memo to maintain the same performance optimization that PureComponent provided

How was this change tested?

• All tests are passing

Checklist

• I have read https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md
• I have signed all commits
• I have added unit tests for the new functionality
• I have run lint and test steps successfully
  • for jaeger: make lint test
  • for jaeger-ui: npm run lint and npm run test

[graphite-app]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.39%. Comparing base (dd65633) to head (fef474e).
Report is 12 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2856      +/-   ##
==========================================
- Coverage   97.39%   97.39%   -0.01%     
==========================================
  Files         256      256              
  Lines        7975     7973       -2     
  Branches     2084     2009      -75     
==========================================
- Hits         7767     7765       -2     
  Misses        208      208              

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