Add Intersphinx

[dangunter]

Add intersphinx to example notebooks

Fixes #131 (see also IDAES/idaes-pse#1468)

Intersphinx is a Sphinx extension automatically (or explicitly) links to external Sphinx project documentation. Since our example documentation is generated by JupyterBook and JB uses Sphinx underneath, it is possible to use Intersphinx, with the Myst markdown syntax, with some rather simple configuration changes.

For example, the following adds a link into the IDAES documentation from a notebook markdown cell:

This tutorial will take you through using the {py:class}`DiagnosticsToolbox <idaes.core.util.model_diagnostics.DiagnosticsToolbox>` to debug a number of issues

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📚 Documentation preview 📚: https://idaes-examples--132.org.readthedocs.build/en/132/

[dangunter]

The script under scripts/update_intersphinx_mapping.py will pull the shared PSE+ Intersphinx mapping (so docs links are synced) and modify the _config.yml under the notebooks directory. It can also run the command to propagate those updates to the conf.py file.

e.g. from the root directory:

python scripts/update_intersphinx_mapping.py -d idaes_examples/notebooks -c

[dangunter]

@lbianchi-lbl I removed the script and added a Pyomo URL. Did this via the web interface (!) so need to wait for CI to check my work.

[lbianchi-lbl]

The (only, for the time being) reference using Intersphinx seems to work correctly: