support to generate example for application/x-www-form-urlencoded

[dspo]

…coded

What type of this PR

Add one of the following kinds:
/kind feature

What this PR does / why we need it:

• supprot to generate example for application/x-www-form-urlencoded
• do not validate the value of the filed format in OAS3, because it is an open value

Which issue(s) this PR fixes:

• Fixes #your-issue_number
• [Erda Cloud Issue Link](paste your link here)

Specified Reviewers:

/assign @your-reviewer

ChangeLog

Language	Changelog
🇺🇸 English
🇨🇳 中文

Need cherry-pick to release versions?

Add comment like /cherry-pick release/1.0 when this PR is merged.

For details on the cherry pick process, see the cherry pick requests section under CONTRIBUTING.md.

[codecov]

Codecov Report

Merging #1632 (b5f2ef1) into master (75ac22c) will increase coverage by 0.04%.
The diff coverage is 40.98%.

@@            Coverage Diff             @@
##           master    #1632      +/-   ##
==========================================
+ Coverage   12.98%   13.03%   +0.04%     
==========================================
  Files        1042     1042              
  Lines      108746   108776      +30     
==========================================
+ Hits        14121    14174      +53     
+ Misses      93347    93335      -12     
+ Partials     1278     1267      -11     

Impacted Files	Coverage Δ
pkg/swagger/oas3/validate.go	0.00% <0.00%> (ø)
pkg/swagger/oas3/gen_example.go	44.30% <45.45%> (+44.30%)	⬆️
pkg/parser/pipelineyml/visitor_ref_op.go	46.23% <0.00%> (-0.54%)	⬇️
modules/core-services/services/project/project.go	7.59% <0.00%> (+0.76%)	⬆️
...ules/scheduler/executor/plugins/k8s/statefulset.go	52.28% <0.00%> (+5.24%)	⬆️

[johnlanni]

/approve