fix parsing bug affected by fmt

[sdghchj]

Describe the PR

1. During parsing comments, use func unicode.IsSpace instead of a space ' ' to split.
2. When spliting comments during formating, don't split nested pair characters such as [] in generics example A[[]B,[]C]

Relation issue
#1397

[codecov]

Codecov Report

Base: 95.16% // Head: 95.17% // Increases project coverage by +0.00% 🎉

Coverage data is based on head (9a9c6c5) compared to base (e5d507d).
Patch coverage: 100.00% of modified lines in pull request are covered.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1398   +/-   ##
=======================================
  Coverage   95.16%   95.17%           
=======================================
  Files          15       16    +1     
  Lines        3060     3107   +47     
=======================================
+ Hits         2912     2957   +45     
- Misses         85       86    +1     
- Partials       63       64    +1     

Impacted Files	Coverage Δ
formatter.go	100.00% <100.00%> (ø)
operation.go	96.26% <100.00%> (+0.02%)	⬆️
parser.go	94.13% <100.00%> (+0.07%)	⬆️
utils.go	100.00% <100.00%> (ø)
field_parser.go	98.00% <0.00%> (-0.58%)	⬇️
schema.go	97.70% <0.00%> (+0.05%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report at Codecov.
📢 Do you have feedback about the report comment? Let us know in this issue.