ref(metrics): move eap meta from API to sentry_metrics

[shellmayr]

To avoid mixing abstraction levels, move EAP meta to function in sentry_metrics

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 83.33333% with 2 lines in your changes missing coverage. Please review.

:white_check_mark: All tests successful. No failed tests found.

Files	Patch %	Lines
...try/sentry_metrics/querying/eap/metrics_details.py	77.77%	1 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #76536      +/-   ##
==========================================
+ Coverage   79.96%   79.99%   +0.02%     
==========================================
  Files        7064     6895     -169     
  Lines      316313   307973    -8340     
  Branches    52794    52794              
==========================================
- Hits       252953   246349    -6604     
+ Misses      62922    60601    -2321     
- Partials      438     1023     +585