lightsail: Add L2 construct for Instance

[mu7889yoon]

Is your feature request related to a problem? Please describe.
CloudFormation supports Instance for Lightsail.

but there are no L2 Construct.

Would you be willing to help with a PR?

• Yes, absolutely
• Yes, with some guidance
• Unfortunately no time :'-(

Describe the solution you'd like

Add Instance L2 construct

Describe alternatives you've considered

Use L1 construct

Additional context

CloudFormation support other lightsail features. but this issue is scoped specifically to the Lightsail Instance.