Extract file-finding for partition info reading.

[delucchi-cmu]

Change Description

Related to astronomy-commons/lsdb#107

Extracts the logic to pick which partition info file to read to just exist in the PartitionInfo, just for code isolation. Follow-up PRs will potentially add new files/formats for storing the partition info for faster access.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (3358fbc) 99.72% compared to head (a8cb2b9) 100.00%.
Report is 4 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff             @@
##             main      #196      +/-   ##
===========================================
+ Coverage   99.72%   100.00%   +0.27%     
===========================================
  Files          53        53              
  Lines        1811      1831      +20     
===========================================
+ Hits         1806      1831      +25     
+ Misses          5         0       -5     

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[github-actions]

Before [ffa8352] <v0.2.3>	After [d9606b9]	Ratio	Benchmark (Parameter)
300±20ms	312±10ms	1.04	benchmarks.MetadataSuite.time_load_partition_info_order6
1.12±0.02s	1.14±0.01s	1.02	benchmarks.MetadataSuite.time_load_partition_info_order7
641±3ms	642±4ms	1	benchmarks.Suite.time_pixel_tree_creation
125±0.6ms	125±0.8ms	1	benchmarks.time_test_alignment_even_sky
1.85±0.02s	1.84±0.01s	0.99	benchmarks.MetadataSuite.time_load_partition_join_info
98.4±0.3ms	97.7±0.7ms	0.99	benchmarks.time_test_cone_filter_multiple_order

Click here to view all benchmarks.

[camposandro]

Looks good, left some minor comments!