fix(entity): add default options to entity adapter when undefined is passed

[markostanimirovic]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

const {
  selectId, // selectId is undefined instead of the default id selector
  sortComparer, // sortComparer is undefined instead of false
} = createEntityAdapter<Entity>({
  selectId: undefined,
  sortComparer: undefined,
});

What is the new behavior?

const {
  selectId, // selectId is equal to default id selector
  sortComparer, // sortComparer is false
} = createEntityAdapter<Entity>({
  selectId: undefined,
  sortComparer: undefined,
});

Does this PR introduce a breaking change?

[ ] Yes
[x] No

[netlify]

✔️ Deploy Preview for ngrx-io canceled.
Built without sensitive environment variables

🔨 Explore the source changes: 79c2e97

🔍 Inspect the deploy log: https://app.netlify.com/sites/ngrx-io/deploys/61de0c9dc61f3f000858aab4

[ngrxbot]

Preview docs changes for 79c2e97 at https://previews.ngrx.io/pr3287-79c2e97b/

[timdeschryver]

TIL, I thought that this wasn't allowed with TS (either by default or with strict).
But to enable this, you have to enable the exactOptionalPropertyTypes option.