Updated notebooks to use regular web api for batch mode solver

[tomflexcompute]

Happened to find some time today so decided to address this PR #231 (comment) sooner rather than later. Hope it doesn't cause conflicts when merging to develop later.

There are two charge solver notebooks that I haven't modified yet, but they will be revamped soon to use our own charge solver right? They can be modified together. There is also a heat solver notebook that I haven't modified either. Will that notebook be modified due to some API change in 2.8.0 or I should just modify it now?

[momchil-flex]

Thanks @tomflexcompute! I asked @marc-flex to handle the substitution in the heat/charge notebooks. There's also one notebook which is currently only on develop which uses this (the radiative loss analysis). We can fix this too eventually after merging develop in pre/2.8 (for now we're not doing that because of the docs build issue.. too many notebooks :D )

[tomflexcompute]

No problem I can fix that later on.

[e-g-melo]

Hi @tomflexcompute! Thanks for updating these notebooks. A single approach for running batches is a great improvement in usability!

[tomflexcompute]

I suppose at some point we need to update all the single mode solver runs to use web.run(), which requires updating many more notebooks but that's not very critical at he moment so we can update them closer to the 2.8 release. Shall I merge this PR as it is @momchil-flex ?

[marc-flex]

I was going to add here a modification to the MZ interferometer, but I can I move it to a different branch 👍

[tomflexcompute]

I was going to add here a modification to the MZ interferometer, but I can I move it to a different branch 👍

Oh I see please feel free to go ahead and update it here. Whatever is more convenient is fine.

[momchil-flex]

I discussed with @marc-flex that he'll keep the heat/charge notebooks in a separate PR as there are other updates too.