fix(react-form): ensure FormApi.handleSubmit returns a promise again (#1924)

* fix(react-form): fix handleSubmit no longer returning a promise

* Fix FormApi.handleSubmit to return a promise

* ci: apply automated fixes and generate docs

---------

Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

Author: LeCarbonator

.changeset/serious-lamps-draw.md

@@ -0,0 +1,5 @@
+---
+'@tanstack/react-form': patch
+---
+
+fix(react-form): ensure `FormApi.handleSubmit` returns a promise again

packages/react-form/src/useForm.tsx

@@ -228,7 +228,7 @@ export function useForm<
     > = {
       ...formApi,
       handleSubmit: ((...props: never[]) => {
-        formApi._handleSubmit(...props)
+        return formApi._handleSubmit(...props)
       }) as typeof formApi.handleSubmit,
       // We must add all `get`ters from `core`'s `FormApi` here, as otherwise the spread operator won't catch those
       get formId(): string {