MAINT use public import for metadata routing

[glemaitre]

Let's use public module for metadata routing and let's monkey patch the methods supported next to our base class where fit_resample is declared.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.92%. Comparing base (e32819e) to head (b439c4f).
Report is 24 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1113      +/-   ##
==========================================
+ Coverage   92.98%   93.92%   +0.93%     
==========================================
  Files         105       54      -51     
  Lines        8323     3636    -4687     
  Branches     1288      486     -802     
==========================================
- Hits         7739     3415    -4324     
+ Misses        465      124     -341     
+ Partials      119       97      -22     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.