fix: reject calling suite function inside test (#9198)

Author: hi-ogawa

packages/runner/src/suite.ts

@@ -538,6 +538,12 @@ function createSuite() {
     factoryOrOptions?: SuiteFactory | TestOptions,
     optionsOrFactory?: number | SuiteFactory,
   ) {
+    if (getCurrentTest()) {
+      throw new Error(
+        'Calling the suite function inside test function is not allowed. It can be only called at the top level or inside another suite function.',
+      )
+    }
+
     let mode: RunMode = this.only
       ? 'only'
       : this.skip

test/core/test/nested-suite.test.ts

@@ -25,3 +25,9 @@ describe('a', () => {
 it('visited', () => {
   expect(visited).toBe(true)
 })
+
+it('suite inside test should throw', () => {
+  expect(() => {
+    describe('inside test', () => {})
+  }).toThrowErrorMatchingInlineSnapshot(`[Error: Calling the suite function inside test function is not allowed. It can be only called at the top level or inside another suite function.]`)
+})