fix(react-jsonschema-form): withTheme forwards the ref to the form

[zepatrik]

As someone noted here the current typing does not reflect the forwarding of the ref to the form component.

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If changing an existing definition:

• Provide a URL to documentation or source code which provides context for the suggested changes: add forwardRef to withTheme rjsf-team/react-jsonschema-form#1498
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[typescript-bot]

@zepatrik Thank you for submitting this PR!

This is a live comment which I will keep updated.

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Because you edited one package and updated the tests (👏), I can help you merge this PR once someone else signs off on it.

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---

Diagnostic Information: What the bot saw about this PR

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[typescript-bot]

🔔 @iamdanfox @iplus26 @phbou72 @LucianBuzzo @sthenault @sbusch @medfreeman @saadtazi @agustin107 @chanceaclark @ogdentrod @andrenguyener @QingqiShi — please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

[typescript-bot]

👋 Hi there! I’ve run some quick measurements against master and your PR. These metrics should help the humans reviewing this PR gauge whether it might negatively affect compile times or editor responsiveness for users who install these typings.

Let’s review the numbers, shall we?

Comparison details 📊

	master	#46102	diff
Batch compilation
Memory usage (MiB)	123.5	123.5	0.0%
Type count	23993	23956	0%
Assignability cache size	7012	6986	0%
Language service
Samples taken	368	374	+2%
Identifiers in tests	368	374	+2%
getCompletionsAtPosition
Mean duration (ms)	613.1	612.8	-0.1%
Mean CV	7.3%	7.4%
Worst duration (ms)	847.6	809.4	-4.5%
Worst identifier	element	onBlur
getQuickInfoAtPosition
Mean duration (ms)	602.9	603.6	+0.1%
Mean CV	7.5%	7.8%	+3.5%
Worst duration (ms)	769.5	867.5	+12.7%
Worst identifier	element	element

It looks like nothing changed too much. I won’t post performance data again unless it gets worse.

[zepatrik]

Actually the package starting with v2+ has it's own type definitions and is published as @rjsf/core. The change forwarding the ref is actually not in the last v1 release that this type definition refers to so I'm closing this PR. Instead this is fixed in rjsf-team/react-jsonschema-form#1915