Add batched circuit to documentation

[nathanshammah]

Issue Description

We do not report on batched quantum circuits. Batching has been used by @vprusso for example in Ref. [1]. The Research folder notebook related to that publication does not contain a batched example though [2].

Proposed Solution

Add a simple batching snippet and explanation in the documentation, such as in the user guide (could even be in core concepts, given how important it is) or as a new tutorial.

Additional References

[1] https://arxiv.org/abs/2210.07194
[2] https://github.com/unitaryfund/research/tree/main/qem-on-hardware