Fix pytest test collection on default install

[cdanis]

As is, with a default poetry install, a simple poetry pytest run will encouter import errors while reading the test files themselves -- which causes pytest to fatally error during test collection, meaning no tests are run.

[dougtoppin]

As a test, I opened the PR into a gitpod workspace and did the following.
Note that both --all-groups and --all-extras were necessary to get all tests to pass.
If either were not included test failures did occur.

• poetry install --all-groups
• poetry install --all-extras
• poetry run pytest

Got the following output from pytest:

============================================================================ test session starts =============================================================================
platform linux -- Python 3.12.9, pytest-8.3.3, pluggy-1.5.0
rootdir: /workspace/meshtastic-python
configfile: pytest.ini
plugins: anyio-4.6.2.post1, cov-5.0.0, hypothesis-6.119.1, dash-2.18.2
collected 306 items / 75 deselected / 231 selected                                                                                                                           

meshtastic/tests/test_analysis.py .                                                                                                                                    [  0%]
meshtastic/tests/test_init.py ...                                                                                                                                      [  1%]
meshtastic/tests/test_main.py ............................................................................                                                             [ 34%]
meshtastic/tests/test_mesh_interface.py ...............................................                                                                                [ 54%]
meshtastic/tests/test_node.py ....................                                                                                                                     [ 63%]
meshtastic/tests/test_remote_hardware.py .......                                                                                                                       [ 66%]
meshtastic/tests/test_serial_interface.py ...                                                                                                                          [ 67%]
meshtastic/tests/test_stream_interface.py ..                                                                                                                           [ 68%]
meshtastic/tests/test_tcp_interface.py ...                                                                                                                             [ 70%]
meshtastic/tests/test_tunnel.py ..............                                                                                                                         [ 76%]
meshtastic/tests/test_util.py .......................................................                                                                                  [100%]

==================================================================== 231 passed, 75 deselected in 21.27s =====================================================================

Workspace details:

• Ubuntu 22.04.5 LTS
• Python 3.12.9
• Poetry (version 2.0.1)
• pytest 8.3.3

I had a suggestion if there is interest.
It can be helpful with PRs to include a few more details.
This is useful for people both to know how it was tested and as a reference for people submitting future PRs to know how they should test.
A pull request template md can be created which gives a new submitter a starting point for what to do.
That template could include environment and version information, steps that were performed, and expected output/results.
It might also include a description of unit or other tests that were added.

I am not sure if this is helpful or not, but I have found this useful in the past and it can reduce review time.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.14%. Comparing base (ed908fc) to head (b42d338).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #749   +/-   ##
=======================================
  Coverage   60.14%   60.14%           
=======================================
  Files          24       24           
  Lines        4062     4062           
=======================================
  Hits         2443     2443           
  Misses       1619     1619           

Flag	Coverage Δ
unittests	60.14% <ø> (ø)

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[cdanis]

As discussed on Discord, I'll also create new pytest markers for analytics, powermon, and tunnel, and make them default-excluded (like the other ones with 'optional dependencies' like "two radios connected over USB" are).