[TEST] Covering useDeleteOne relations optimistic cache behavior (#10238)

## Introduction
Added coverage on the `useDeleteOneRecord` hooks, especially its
optimistic behavior feature.
Introduced a new testing tool `InMemoryTestingCacheInstance` that has
builtin very basic expectors in order to avoid future duplication when
covering others record hooks `update, create, destroy` etc etc

## Notes
Added few comments in this PR regarding some builtin functions I've
created around companies and people mocked object model and that I think
could be cool to spread and centralize within a dedicated "class
template"

Also put in light that unless I'm mistaken some tests are running on
`RecordNode` and not `RecordObject`

Took few directions on my own that as I always I would suggestion nor
remarks on them !

Let me know

## Misc
- Should we refactor `useDeleteOneRecord` tests to follow `eachTesting`
pattern ? => I feel like this is inappropriate as this hooks is already
high level, the only plus value would be less tests code despite
readability IMO

packages/twenty-front/src/modules/object-record/cache/utils/__tests__/getRecordNodeFromRecord.test.ts

@@ -1,11 +1,11 @@
 import { ObjectMetadataItem } from '@/object-metadata/types/ObjectMetadataItem';
 
-import { getPeopleMock } from '~/testing/mock-data/people';
+import { getPeopleRecordConnectionMock } from '~/testing/mock-data/people';
 
 import { generatedMockObjectMetadataItems } from '~/testing/mock-data/generatedMockObjectMetadataItems';
 import { getRecordNodeFromRecord } from '../getRecordNodeFromRecord';
 
-const peopleMock = getPeopleMock();
+const peopleMock = getPeopleRecordConnectionMock();
 
 describe('getRecordNodeFromRecord', () => {
   it('computes relation records cache references by default', () => {