Add @dashpole (David Ashpole) as a maintainer

[MadVikingGod]

Requirements

• Deep understanding of the technical goals and direction of the project
• Deep understanding of the technical domain (specifically the language) of the project
• Sustained contributions to design and direction
• Sign-off by all existing maintainers

Follow up tasks

• Add to GitHub groups
• Merge similar changes in the opentelemetry-go-contrib repository (Add David Ashpole as a maintainer opentelemetry-go-contrib#4822)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (279c549) 82.3% compared to head (3e191a9) 82.3%.

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #4830     +/-   ##
=======================================
- Coverage   82.3%   82.3%   -0.1%     
=======================================
  Files        226     226             
  Lines      18421   18421             
=======================================
- Hits       15166   15164      -2     
- Misses      2969    2971      +2     
  Partials     286     286             

see 1 file with indirect coverage changes