feat(igxGrid): Row Pinning + Paging integration

[mddragnev]

Related #6640

Additional information (check all that apply):

• Bug fix
• New functionality
• Documentation
• Demos
• CI/CD

Checklist:

• All relevant tags have been applied to this PR
• This PR includes unit tests covering all the new code
• This PR includes API docs for newly added methods/properties
• This PR includes feature/README.MD updates for the feature docs
• This PR includes general feature table updates in the root README.MD
• This PR includes CHANGELOG.MD updates for newly added functionality
• This PR contains breaking changes
• This PR includes ng update migrations for the breaking changes
• This PR includes behavioral changes and the feature specification has been updated with them

[MayaKirova]

@mddragnev @ChronosSF
If record is pinned initially, before rows are rendered, for example:
ngAfterViewInit() {
this.grid1.pinRow('FRANS');
}

Then the page size is incorrect.

With following settings: <igx-grid [paging]='true' [perPage]='5'

6 records are rendered.