test(react): improve ErrorBoundaryGroup test code (#1157)

# Overview

Hi, I've been looking at the `ErrorBoundaryGroup` test code and trying
to improve it.

- I changed `Throw.reset()` to be managed by `beforeEach`.
- `useErrorBoundaryGroup` related tests only have tests that fail. I add
success case.

**Question**

[Related
Code](https://github.com/toss/suspensive/blob/cbbb6ffe649cfd4442da5fcf55e92d0afdf0fb3c/packages/utils/src/test-utils/index.tsx#L4-L26)

The `current` value of `isNeedThrowGlobal` used by the `Throw` object
doesn't seem to change.
There doesn't seem to be anything currently happening that would cause
`isNeedThrowGlobal.current = true`.

<img width="1142" alt="스크린샷 2024-07-28 오후 6 54 04"
src="https://github.com/user-attachments/assets/7d3b874a-2407-4684-98f6-7c6638b8d79a">

So the absence of `Throw.reset()` in the current test doesn't seem to
change the result of the test.
Was this code added for safety?

Thanks. 🙇‍♂️

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    A clear and concise description of what this pr is about.
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## PR Checklist

- [x] I did below actions if need

1. I read the [Contributing
Guide](https://github.com/toss/suspensive/blob/main/CONTRIBUTING.md)
2. I added documents and tests.

Co-authored-by: Jonghyeon Ko <[email protected]>

packages/react/src/ErrorBoundaryGroup.spec.tsx

@@ -13,6 +13,8 @@ const innerErrorBoundaryCount = 3
 const resetButtonText = 'reset button'
 
 describe('<ErrorBoundaryGroup/>', () => {
+  beforeEach(() => Throw.reset())
+
   it('should reset all ErrorBoundaries in children', async () => {
     render(
       <ErrorBoundaryGroup>
@@ -31,7 +33,6 @@ describe('<ErrorBoundaryGroup/>', () => {
 
     expect(screen.getAllByText(TEXT).length).toBe(innerErrorBoundaryCount)
     await waitFor(() => expect(screen.getAllByText(ERROR_MESSAGE).length).toBe(innerErrorBoundaryCount))
-    Throw.reset()
 
     fireEvent.click(screen.getByRole('button', { name: resetButtonText }))
     expect(screen.getAllByText(TEXT).length).toBe(innerErrorBoundaryCount)
@@ -58,7 +59,6 @@ describe('<ErrorBoundaryGroup/>', () => {
 
     expect(screen.getAllByText(TEXT).length).toBe(innerErrorBoundaryCount)
     await waitFor(() => expect(screen.getAllByText(ERROR_MESSAGE).length).toBe(innerErrorBoundaryCount))
-    Throw.reset()
 
     fireEvent.click(screen.getByRole('button', { name: resetButtonText }))
     expect(screen.getAllByText(TEXT).length).toBe(innerErrorBoundaryCount - 1)
@@ -67,7 +67,21 @@ describe('<ErrorBoundaryGroup/>', () => {
 })
 
 describe('useErrorBoundaryGroup', () => {
-  it('should throw error without ErrorBoundaryGroup in parent', () => {
+  it('should guarantee hook calling position is in children of ErrorBoundaryGroup', () => {
+    expect(
+      render(
+        <ErrorBoundaryGroup>
+          {createElement(() => {
+            useErrorBoundaryGroup()
+            return <></>
+          })}
+          <ErrorBoundary fallback={ERROR_MESSAGE}>
+            <>{TEXT}</>
+          </ErrorBoundary>
+        </ErrorBoundaryGroup>
+      ).getByText(TEXT)
+    ).toBeInTheDocument()
+
     expect(() =>
       render(
         createElement(() => {
@@ -76,6 +90,7 @@ describe('useErrorBoundaryGroup', () => {
         })
       )
     ).toThrow(Message_useErrorBoundaryGroup_this_hook_should_be_called_in_ErrorBoundary_props_children)
+
     try {
       render(
         createElement(() => {