Reorder TOC

[kaelynj]

This change works to reorder the left nav to more clearly differentiate "Qiskit" from IBM Quantum related services.

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[frankharkins]

Bump (to prevent preview from being cleaned up)

[abbycross]

@kaelynj I see that the "Create a provider" page appears twice - once under the Qiskit section, and once under the Qiskit SDK section (which is under Open-source resources in Additional resources).

1. Do we keep it in one of these two places?
2. Would this count as an integration that could go under the Integrations section instead of either of those?
3. It also raises the question as to whether the Qiskit SDK section should move out of the Open-source resources section in Additional resources, and get moved into the Qiskit section?