Hide the maximum number of results editor when ES is enabled

Currently, when configuring a content view/page provider, if the "use ES index" is activated, the editor to configure the maximum number of results is displayed as a read-only (even though the styling is not very clear).

=> It would be nice to either grey out the option, or make it disappear to clarify that it can't be used in this case, otherwise people might be tempted to believe it's a bug although it's not.