Give Sprites Comment Attribute and allow comment duplication

[Victor-Crawshaw]

Resolves

Resolves scratchfoundation/scratch-gui#3687

Proposed Changes

Create comment attribute in Sprite, and modify duplicate() method to copy over that comment attribute. Targets now take comments as an argument so that they may be copied over in Rendered Target as well.

Duplicate.Comments.Demo.mp4

Reason for Changes

Comments should be an attribute in Sprite because if comments want to be duplicated when sprites are duplicated, then it would make sense for them to be part of a sprite, rather than merely part of a target,

Test Coverage

Added unit test to ensure comments are duplicated along with a sprite, also made sure all other tests still pass.

[github-actions]

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[Victor-Crawshaw]

I have read the CLA Document and I hereby sign the CLA

[Victor-Crawshaw]

recheck