feat: add rollout api

[zoumo]

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

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

6. Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[github-actions]

license-eye has checked 67 files.

Valid	Invalid	Ignored	Fixed
27	1	39	0

Click to see the invalid file list

• rollout/v1alpha1/traffic_route_types.go

Use this command to fix any missing license headers

```bash

docker run -it --rm -v $(pwd):/github/workspace apache/skywalking-eyes header fix

</details>