disable horizontal scroll in virtual scroller

#### Please describe the feature you would like to request.
I would like an input for `cdk-virtual-scroll-viewport` directive which disabled the horizontal scroll, or in other words sets the width of `cdk-virtual-scroll-content-wrapper` to 100%, as opposed to just setting the min-width by default, to enable horizontal scrolling.

#### What is the use-case or motivation for this proposal?
Sometimes you have long list values and you want them to fit the width of your list and be displayed with ellipses, as opposed to having horizontal scroll. Because of how this component is implemented, putting the `min-width: 100%` in `cdk-virtual-scroll-content-wrapper` prevents me from limiting the width of the items by the parent's width.

#### Is there anything else we should know?
No.

Beginne mit der im Issue beschriebenen cdk-virtual-scroll-viewport-Direktive und dem Styling von cdk-virtual-scroll-content-wrapper. Verfolge, wie der Wrapper derzeit seine Mindestbreite anwendet, und identifiziere das erforderliche Eingabeverhalten, um horizontales Scrollen zu verhindern. Erledigt bedeutet, dass lange Listenwerte in die Breite des übergeordneten Elements passen und Auslassungspunkte anzeigen können, ohne horizontal zu scrollen.

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