core: session - AOT build fails when a config object is passed to StarkSessionModule.forRoot()

[christophercr]

I'm submitting a...

[ ] Regression (a behavior that used to work and stopped working in a new release)
[X] Bug report  
[ ] Feature request
[ ] Documentation issue or request
[ ] Support request => Please do not submit support request here, instead see https://github.com/NationalBankBelgium/stark/blob/master/CONTRIBUTING.md#got-a-question-or-problem

Current behavior

With the changes done in #766, if a custom config is passed to the StarkSessionModule.forRoot() in the client application, the PROD AOT build fails with the following error:

ERROR in Error during template compile of 'StarkSessionModule'
  Function calls are not supported in decorators but 'starkSessionConfigFactory' was called.

The issue is explained here: angular/angular#14707

Expected behavior

The PROD AOT build should succeed regardless of whether a custom config is passed to Stark modules or not.

Minimal reproduction of the problem with instructions

Pass a custom config to the StarkSessionModule.forRoot() in the AppModule for example:

@NgModule({
    bootstrap: [AppComponent],
    declarations: [AppComponent, ...],
    imports: [
        ...
        StarkSessionModule.forRoot({
            loginStateName: "some login state"
        }),
   ],
   providers: [...]
})
export class AppModule { }

What is the motivation / use case for changing the behavior?

Stable and successful PROD AOT builds including Stark modules.

Environment

Angular version: 6.1.9
Stark version: 10.0.0-beta.0