Update Safari + iOS data for disabled <optgroup>

[telic]

Summary

Record incomplete support for the disabled attribute on optgroup elements in desktop Safari v6 and current versions of iOS Safari.

Test results and supporting details

@caugner created a JS Bin test case and was able to reproduce back to iOS 11.2.

I tested in:

• Safari 17.6 on MacOS 12.7.6 - passes
• Safari 18.4 on MacOS 15.4.1 - passes
• iOS 18.3.1 - fails

Commit history found from bug 87614 suggests this issue was likely present in desktop Safari 6 (introduced in 536.11), but fixed by version 7 (fix merged in 537.43.1). I'm unable to test whether it was actually working properly earlier.

There is an unresolved bug for iOS and iPadOS.

Related issues

Fixes #26219

[github-actions]

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[caugner]

Great start, thanks! 🙌

Unfortunately, I missed that for HTML attributes, we just set version_added: false if there is no effect (rather than marking support as partial), but can add notes to be explicit.

However, we should also update api.HTMLOptGroupElement.disabled here, similar to HTMLInputElement.webkitdirectory, where being able to set (and read) the property is considered partial_implementation (even if there is no other observable effect):

browser-compat-data/api/HTMLInputElement.json

Lines 3269 to 3278 in b5295a8

	"safari_ios": [
	{
	"version_added": "18.4"
	},
	{
	"version_added": "11.3",
	"partial_implementation": true,
	"notes": "The property can be set, but has no effect (see [bug 271705](https://webkit.org/b/271705))."
	}
	],

I tested back to iOS 4.3 (with this test), and the disabled property of HTMLOptGroupElement can be set (and read), so we can set version_added: "≤4.3" with partial_implementation: true and notes: "The property can be set, but has no effect (see [bug 227042](https://webkit.org/b/227042))."

[caugner]

@telic Please let me know if you have any questions about my review comments, of if you would like to me to finish up the PR.