This adds a new rule `InvalidPyprojectToml` that lints pyproject.toml by checking if https://github.com/PyO3/pyproject-toml-rs can parse it. This means the linting is currently very basic, e.g. we don't check whether the name is actually a valid python project name or appropriately normalized. It does catch errors e.g. with invalid dependency requirements or problems withs the license specifications. It is open to be extended in the future (validate name, SPDX expressions, classifiers, ...), either in ruff or in pyproject-toml-rs.
Test plan:
```
scripts/ecosystem_all_check.sh check --select RUF200
```
This lead to a bunch of
```
RUF200 Failed to parse pyproject.toml: missing field `name`
```
(e.g. https://github.com/amitsk/fastapi-todos/blob/main/pyproject.toml) which is indeed invalid (https://packaging.python.org/en/latest/specifications/declaring-project-metadata/#specification).
Filtering those out, the following other problems were found by `cd target/ecosystem_all_results/ && rg RUF200`:
```
UCL-ARC:rred-reports.stdout.txt
1:pyproject.toml:27:16: RUF200 Failed to parse pyproject.toml: Version specifier `>='3.9'` doesn't match PEP 440 rules
EndlessTrax:python-start-project.stdout.txt
1:pyproject.toml:14:16: RUF200 Failed to parse pyproject.toml: Expected package name starting with an alphanumeric character, found '#'
redjax:gardening-api.stdout.txt
1:pyproject.toml:7:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
ajslater:codex.stdout.txt
2: 3:17 RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
LDmitriy7:404_AvatarsBot.stdout.txt
1:pyproject.toml:3:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
ajslater:comicbox.stdout.txt
1:pyproject.toml:3:17: RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
manueldevillena:forecast-earnings.stdout.txt
1:pyproject.toml:24:12: RUF200 Failed to parse pyproject.toml: Expected one of `@`, `(`, `<`, `=`, `>`, `~`, `!`, `;`, found `^`
redjax:ohio_utility_scraper.stdout.txt
1:pyproject.toml:11:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
agronholm:typeguard.stdout.txt
1:pyproject.toml:40:8: RUF200 Failed to parse pyproject.toml: Expected a valid marker name, found 'python_implementation'
cyuss:decathlon-turnover.stdout.txt
1:pyproject.toml:7:12: RUF200 Failed to parse pyproject.toml: invalid type: string "Youcef", expected a table with 'name' and 'email' keys
ajslater:boilerplate.stdout.txt
1:pyproject.toml:3:17: RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
kaparoo:lightning-project-template.stdout.txt
1:pyproject.toml:56:16: RUF200 Failed to parse pyproject.toml: You can't mix a >= operator with a local version (`+cu117`)
dijital20:pytexas2023-decorators.stdout.txt
1:pyproject.toml:5:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
pfouque:django-anymail-history.stdout.txt
1:pyproject.toml:137:12: RUF200 Failed to parse pyproject.toml: Version specifier `> = 1.2.0` doesn't match PEP 440 rules
pfouque:django-fakemessages.stdout.txt
1:pyproject.toml:130:12: RUF200 Failed to parse pyproject.toml: Version specifier `> = 1.2.0` doesn't match PEP 440 rules
pypa:build.stdout.txt
1:tests/packages/test-invalid-requirements/pyproject.toml:2:12: RUF200 Failed to parse pyproject.toml: Expected one of `@`, `(`, `<`, `=`, `>`, `~`, `!`, `;`, found `i`
4:tests/packages/test-no-requires/pyproject.toml:1:1: RUF200 Failed to parse pyproject.toml: missing field `requires`
UnoYakshi:FRAAND.stdout.txt
2: 3:11 RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
DHolmanCoding:python-template.stdout.txt
1:pyproject.toml:22:1: RUF200 Failed to parse pyproject.toml: missing field `requires`
```
Overall, this emitted errors in 43 out of 3408 projects (`rg -c RUF200 target/ecosystem_all_results/ | wc -l`)
Co-authored-by: Micha Reiser <micha@reiser.io>
