Generalize assignment of beam coordinate var attributes

[emiliom]

Unified where the attributes for the core beam coordinate variables (frequency, ping_time, range_bin) are set. I've created a new DEFAULT_BEAM_COORD_ATTRS dict in set_groups_base.py that declares these common attributes and their values, then import that variable in the various set_groups_x.py modules. This PR implements that change for ek60, ek80, azfp.This abstraction/centralization will reduce the potential for variability across sensors and make it a tiny, tiny bit easier to roll out support for new sensors in a consistent fashion.

Also added a long_name attribute to range_bin, partly addressing #373

[codecov-commenter]

Codecov Report

Merging #480 (9ccdf36) into dev (4c77300) will decrease coverage by 4.39%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##              dev     #480      +/-   ##
==========================================
- Coverage   76.66%   72.27%   -4.40%     
==========================================
  Files          38       16      -22     
  Lines        3339     2287    -1052     
==========================================
- Hits         2560     1653     -907     
+ Misses        779      634     -145     

Flag	Coverage Δ
unittests	72.27% <100.00%> (-4.40%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
echopype/convert/set_groups_azfp.py	98.14% <100.00%> (ø)
echopype/convert/set_groups_base.py	88.04% <100.00%> (-2.07%)	⬇️
echopype/convert/set_groups_ek60.py	91.08% <100.00%> (ø)
echopype/convert/set_groups_ek80.py	94.24% <100.00%> (-1.44%)	⬇️
echopype/convert/convert.py	60.00% <0.00%> (-40.00%)	⬇️
echopype/convert/api.py	80.83% <0.00%> (-5.00%)	⬇️
echopype/convert/utils/ek_raw_parsers.py	54.74% <0.00%> (-0.17%)	⬇️
echopype/preprocess/api.py
... and 21 more

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[leewujung]

Thanks @emiliom, this looks great!

One thing I thought of when going through this is that DEFAULT_BEAM_COORD_ATTRS should probably live somewhere else, something like core.py but for convention side of things. Perhaps that's something to be resolved in a more top-down form, related to the pydantic work. For now it seems fine for that to live under set_group_base.py.

On an unrelated note, I noticed that DEFAULT_CHUNK_SIZE is only used for encoding EK60 data. Properly chunking is arguably going to be more important for EK80. I'll submit an issue about that so that we don't forget about that when we get to working on performance-related issues..

[emiliom]

On an unrelated note, I noticed that DEFAULT_CHUNK_SIZE is only used for encoding EK60 data. Properly chunking is arguably going to be more important for EK80. I'll submit an issue about that so that we don't forget about that when we get to working on performance-related issues..

Continuing the unrelated note, I think I noticed that DEFAULT_CHUNK_SIZE is actually declared in two different modules, the same way, But yeah, that's for another issue

[emiliom]

One thing I thought of when going through this is that DEFAULT_BEAM_COORD_ATTRS should probably live somewhere else, something like core.py but for convention side of things. Perhaps that's something to be resolved in a more top-down form, related to the pydantic work. For now it seems fine for that to live under set_group_base.py.

Let's revisit that thought for sure, once we're creating the convention-compliance architecture for 0.6.0

[emiliom]

Thanks for the review. I'll self merge now