Added kinematic methods to Python Link wrapper

[ahcorde]

🦟 Bug fix

Summary

Added kinematic and setkinematic methods to Link Python wrappers. Not included here https://github.com/gazebosim/sdformat/pull/1390/files

Checklist

• Signed all commits for DCO
• Added tests
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
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