Rename gen.go -> cbor_gen.go

[Stebalien]

fixes #380

[Stebalien]

This likely won't conflict with anything outstanding.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.59%. Comparing base (5aa1e01) to head (8a5719f).

❗ There is a different number of reports uploaded between BASE (5aa1e01) and HEAD (8a5719f). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (5aa1e01)	HEAD (8a5719f)
	4	2

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #446      +/-   ##
==========================================
- Coverage   75.96%   68.59%   -7.38%     
==========================================
  Files          43       46       +3     
  Lines        3770     4525     +755     
==========================================
+ Hits         2864     3104     +240     
- Misses        620      891     +271     
- Partials      286      530     +244     

Files	Coverage Δ
certexchange/cbor_gen.go	38.31% <ø> (ø)
certs/cbor_gen.go	32.77% <ø> (ø)
gpbft/cbor_gen.go	30.55% <ø> (ø)

... and 3 files with indirect coverage changes