Add model of karmada

[liangyuanpeng]

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• N
• Y

2. What is the scope of this PR (e.g. component or file name):

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Other

Add model of karmada, and provide crds of policy first.

4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link):

• N
• Y

5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• Unit test
• Integration test
• Benchmark (add benchmark stats below)
• Manual test (add detailed scripts or steps below)
• Other

[liangyuanpeng]

Actually, i have some question at comment for add a new model.

And i have not see the any test for models of this repo.

Remind me if i missed something,Thanks.

[Peefy]

Actually, i have some question at comment for add a new model.

And i have not see the any test for models of this repo.

Remind me if i missed something,Thanks.

We are currently refactoring the testing tool, which is expected to be available in the official version of v0.7.0. At that time, we will improve the process of writing test cases and test cases (expected to write unit tests like Go). cc @amyXia1994

[Peefy]

Thank you for your contribution ❤️. I have left some comments.