🚸 allow using raw RST cells in jupyter notebooks (#558)

## Description

This PR updates the jupyter notebook cleaning pre-commit check to
preserve MIME metadata. This allows to use raw RST cells within jupyter
notebooks, which can be very helpful for using Sphinx references as part
of the documentation.

## Checklist:

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- [x] The pull request only contains commits that are related to it.
- [x] I have added appropriate tests and documentation.
- [x] I have made sure that all CI jobs on GitHub pass.
- [x] The pull request introduces no new warnings and follows the
project's style guidelines.

---------

Signed-off-by: burgholzer <burgholzer@me.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.pre-commit-config.yaml

@@ -35,6 +35,11 @@ repos:
     rev: 3.2.0
     hooks:
       - id: nb-clean
+        args:
+          - --remove-empty-cells
+          - --preserve-cell-metadata
+          - raw_mimetype
+          - --
 
   # Handling unwanted unicode characters
   - repo: https://github.com/sirosen/texthooks

docs/quickstart.ipynb

@@ -393,14 +393,6 @@
     "mqt_qc = qiskit_to_mqt(qiskit_qc)\n",
     "print(mqt_qc)"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "d62ae1fde42917",
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {