fix(ng): use "skipLibCheck": true for legacy igx projects

[Lipata]

The skipLibCheck property is also defined in the standalone templates.

The problem was caught in the CodeGen angular module generated project, where there was a problem with the igniteui-webcomponents library (which is used by igniteui-angular, because the of the wc rating). igniteui-webcomponents is using typescript@5.6. while igniteui-angular is using typescript@5.5 and the following error is shown:

Error: node_modules/igniteui-webcomponents/components/icon/registry/default-map.d.ts:10:16 - error TS2552: Cannot find name 'MapIterator'. Did you mean 'Iterator'?        

10     entries(): MapIterator<[T, U]>;
                  ~~~~~~~~~~~

This is a Typescript API change from 5.5 to 5.6 and because the problem is not related to the generated angular project and it is running successfully, then skipLibCheck: true is a proper solution.

[coveralls]

coverage: 70.414%. remained the same
when pulling 1a955f6 on nalipiev/skip-lib-ng
into aa469c3 on master.