Implicitly registered group routes should be allowed overwritten in default routes

[aldas]

Implicitly registered group routes should be allowed overwritten in default routes. fix issue #3047 and is alternative to #3048

[codecov]

Codecov Report

❌ Patch coverage is 33.33333% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 93.34%. Comparing base (01b45be) to head (4009bb9).
⚠️ Report is 41 commits behind head on master.

Files with missing lines	Patch %	Lines
group.go	0.00%	2 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3049      +/-   ##
==========================================
+ Coverage   93.17%   93.34%   +0.16%     
==========================================
  Files          43       43              
  Lines        4501     4735     +234     
==========================================
+ Hits         4194     4420     +226     
- Misses        189      192       +3     
- Partials      118      123       +5     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.