Make pyproject.toml use PEP621 conventions to specify dependencies

[mfisher87]

For example, we have [tools.poetry.dependencies] instead of a dependencies key under [project]. I think we should use PEP621-compliant configuration here regardless of whether we use Poetry or not.

Related: #374

[Sherwin-14]

@mfisher87 Hey I think poetry uses PEP-621 convention by default. isn't that the case or am I missing something?

[mfisher87]

All of this config is poetry-specific: https://github.com/nsidc/earthaccess/blob/main/pyproject.toml#L37-L103 Although technically compliant with the spec by using poetry's aliases, it's more readable and portable to use the primary field names.

Instead, we should be using the plan dependencies and optional-dependencies data structures (https://peps.python.org/pep-0621/#dependencies-optional-dependencies). Like the example in the PEP621 doc, almost everything should be under the project top-level key. The poetry "extras" section is just another way of expressing an optional dependency group. So we can take all 3 of the poetry-specific sections and combine them to PEP621-standard dependencies and optional-dependencies sections.

[mfisher87]

Maybe this isn't startable without switching away from Poetry? #614 (comment)

[Sherwin-14]

So are we switching to setuptools? What do you think about this?

[mfisher87]

I'm personally for this, but I think we need more input from the rest of the team. Our next hack day may be a good time to chat in real-time to make a decision.