Remove the ability to display multiple tensors in a single space view

[abey79]

What

• Fixes Remove the ability to display multiple tensors in the same space view #6387

Configuring a tensor space view with a query returning more than 1 tensor is now displayed as follows:

This is consistent with the existing behaviour of TextDocument:

This PR is very minimal and aims at status quo consistency. This could be further improved:

• Improve the UI of "mono-entity" space views #6393

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