feat: add the CollaSet generator

[SparkYuan]

…follow the go naming convention

What type of PR is this?

/kind feature

What this PR does / why we need it:

feat: add the CollaSet generator and rename some workload structs to follow the go naming convention

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Additional documentation e.g., design docs, usage docs, etc.:

[coveralls]

Pull Request Test Coverage Report for Build 5899614543

• 68 of 99 (68.69%) changed or added relevant lines in 7 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage decreased (-1.1%) to 70.849%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/cmd/spec/generator.go	1	2	50.0%
pkg/generator/appconfiguration/generator/workload/job_generator.go	0	2	0.0%
pkg/generator/appconfiguration/generator/workload/workload_generator.go	0	3	0.0%
pkg/models/appconfiguration/workload/workload.go	22	34	64.71%
pkg/generator/appconfiguration/generator/workload/service_generator.go	43	56	76.79%

Files with Coverage Reduction	New Missed Lines	%
pkg/cmd/spec/generator.go	1	50.59%

Totals
Change from base Build 5898634175:	-1.1%
Covered Lines:	5296
Relevant Lines:	7475

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💛 - Coveralls

[panshuai-ps]

lgtm