[isort]: support submodules in known_(first|third)_party config options

[astaric]

This is another attempt at #3059. Passes the tests introduced in #3064

I merged the known_first_party and known_third_party members settings into KnownModule so I could add a "shortcut" for all the repositories that do not need this functionality.

Closes #3059.

[github-actions]

PR Check Results

Ecosystem

✅ ecosystem check detected no changes.

Benchmark

Linux

group                                      main                                   pr
-----                                      ----                                   --
linter/all-rules/large/dataset.py          1.00     14.6±0.02ms     2.8 MB/sec    1.00     14.6±0.02ms     2.8 MB/sec
linter/all-rules/numpy/ctypeslib.py        1.00      3.8±0.01ms     4.4 MB/sec    1.01      3.8±0.01ms     4.4 MB/sec
linter/all-rules/numpy/globals.py          1.00    412.9±2.70µs     7.1 MB/sec    1.00    411.3±1.23µs     7.2 MB/sec
linter/all-rules/pydantic/types.py         1.00      6.3±0.01ms     4.0 MB/sec    1.00      6.3±0.02ms     4.0 MB/sec
linter/default-rules/large/dataset.py      1.00      7.7±0.02ms     5.3 MB/sec    1.00      7.8±0.01ms     5.2 MB/sec
linter/default-rules/numpy/ctypeslib.py    1.00   1705.0±2.42µs     9.8 MB/sec    1.01   1723.7±5.08µs     9.7 MB/sec
linter/default-rules/numpy/globals.py      1.00    180.7±0.42µs    16.3 MB/sec    1.01    181.7±1.28µs    16.2 MB/sec
linter/default-rules/pydantic/types.py     1.00      3.6±0.00ms     7.1 MB/sec    1.00      3.6±0.01ms     7.1 MB/sec

Windows

group                                      main                                   pr
-----                                      ----                                   --
linter/all-rules/large/dataset.py          1.00     15.8±0.11ms     2.6 MB/sec    1.03     16.3±0.46ms     2.5 MB/sec
linter/all-rules/numpy/ctypeslib.py        1.00      4.2±0.04ms     4.0 MB/sec    1.01      4.2±0.10ms     3.9 MB/sec
linter/all-rules/numpy/globals.py          1.00   442.9±10.45µs     6.7 MB/sec    1.00    443.1±5.52µs     6.7 MB/sec
linter/all-rules/pydantic/types.py         1.01      7.0±0.14ms     3.7 MB/sec    1.00      6.9±0.09ms     3.7 MB/sec
linter/default-rules/large/dataset.py      1.00      8.2±0.07ms     4.9 MB/sec    1.00      8.3±0.03ms     4.9 MB/sec
linter/default-rules/numpy/ctypeslib.py    1.00  1802.0±30.38µs     9.2 MB/sec    1.00  1798.9±12.53µs     9.3 MB/sec
linter/default-rules/numpy/globals.py      1.00    188.0±2.22µs    15.7 MB/sec    1.01    189.5±5.71µs    15.6 MB/sec
linter/default-rules/pydantic/types.py     1.00      3.8±0.04ms     6.7 MB/sec    1.00      3.8±0.03ms     6.7 MB/sec

[charliermarsh]

Thanks! Nice idea. I went ahead and extended it to the other user-provided modules (known-local-folder and extra-standard-library).