feat: support flag when add oci ref

[zong-zhe]

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

• [x] 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):

• [x] 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):

• [x] N
• [ ] Y

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

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

[coveralls]

Pull Request Test Coverage Report for Build 10594076010

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 14.355%

---

Totals
Change from base Build 10558688220:	0.0%
Covered Lines:	89
Relevant Lines:	620

---

💛 - Coveralls

[Peefy]

We add to support the following pattern for OCI source, the tag denotes the OCI source and version is the version defined in the kcl.mod file. Besides, the --oci flag can be omitted.

kcl mod add [<package>@version] --oci foo --tag bar