Fix React Fragment key issues in multiple components

[Parship999]

Which problem is this PR solving?

While working on some other issues in the codebase, I found additional components with similar React Fragment and key issues. These components had the same React Fragment and key patterns (like in #2812 ) that needed to be solved for consistency and react best practices

Description of the changes

1. KeyValuesTable.tsx

• Changed <> to <React.Fragment key={i}> for proper key attribution

2. highlightMatches.tsx

• Ensured consistent return types by wrapping plain strings in <span> elements
• Added proper keys to all elements returned from map function

3. SearchResults/index.tsx

• Added keys to React.Fragment elements in conditional rendering

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

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.39%. Comparing base (483d574) to head (5b97c8e).
Report is 14 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2823      +/-   ##
==========================================
+ Coverage   97.31%   97.39%   +0.07%     
==========================================
  Files         256      256              
  Lines        7947     7975      +28     
  Branches     2077     2062      -15     
==========================================
+ Hits         7734     7767      +33     
+ Misses        213      208       -5     

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[Parship999]

I created this PR because I noticed several places in the codebase where React fragments were used without keys inside lists, which can cause warnings in React, especially as the codebase evolvess. Acc to me these changes are about following React best practices for keys and rendering

[yurishkuro]

I don't have a problem with the overall direction, I asked specific question.

[Parship999]

Thanks for clarifying, I understand your feedbacks and will make the changes as suggested.