feat(MatTabsModule): Allow alignTabs and stretchTabs on MAT_TABS_CONFIG

[ErickXavier]

Feature Description

As this interfere directly to the design of the elements, I would like to request to include support for alignTabs and stretchTabs on the MAT_TABS_CONFIG configuration.

They can only be set on HTML and should be allow to be set programatically.

Use Case

Whenever we want to set the default design behavior for all Material Tabs.

I believe the use case bellow explains it all:

import {MAT_TABS_CONFIG} from '@angular/material/tabs';
...
@NgModule({
    ...
    providers: [
        {provide: MAT_TABS_CONFIG, useValue: {alignTabs: 'start', stretchTabs: false}}
    ]
})
export class SomeRandomModule {
}```