fix: use subtree option in getAnimations

[kp047i]

Closes #8174

✅ Pull Request Checklist:

• Included link to corresponding React Spectrum GitHub Issue.
• Added/updated unit tests and storybook for this change (for new code or code which already has tests).
• Filled out test instructions.
• Updated documentation (if it already exists for this component).
• Looked at the Accessibility Practices for this feature - Aria Practices

📝 Test Instructions:

🧢 Your Project:

[devongovett]

Thanks! If you have time, would be awesome if you could add an example to storybook with an exit animation on a child element of the popover so we can verify that it works.

[kp047i]

@devongovett
I created a new story example (PopoverChildElementAnimationExample) that shows child element animations working properly.

[snowystinger]

Looks like both entering and exiting are working as expected in Chrome and FF.
In Safari, only exiting is working as expected.

[snowystinger]

This fixes the issue for Safari from what I can tell.

Suggested change

	.react-aria-Popover[data-exiting] .content,
	@starting-style {
	.react-aria-Popover .content {
	opacity: 0;
	}
	}
	.react-aria-Popover[data-exiting] .content,

[kp047i]

@snowystinger
Thanks for the Safari testing!

I've added @starting-style to the Storybook example to address the enter animation issue in Safari. However, this is a CSS-level consideration that developers will need to handle in their own implementations when targeting Safari.
I'm not sure of the best way for React Aria to help developers discover this Safari-specific requirement.

[devongovett]

Yeah I don't think this should be necessary. data-entering should be enough. If it isn't working, then that's a bug we should investigate.