fix reading behaviour with new hats changes

[smcguire-cmu]

Fixes error in unit tests from recent changes to empty catalog filtering in hats

[github-actions]

Before [74a443b]	After [af1b66b]	Ratio	Benchmark (Parameter)
24.5±0.8ms	25.3±0.9ms	1.03	benchmarks.time_polygon_search
977±3ms	984±10ms	1.01	benchmarks.time_create_midsize_catalog
6.56±0.03s	6.58±0.01s	1	benchmarks.time_create_large_catalog
11.8±0.1ms	11.8±0.05ms	0.99	benchmarks.time_box_filter_on_partition
75.8±1ms	75.3±0.7ms	0.99	benchmarks.time_kdtree_crossmatch

Click here to view all benchmarks.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.50%. Comparing base (74a443b) to head (b5d97d8).
Report is 251 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #717   +/-   ##
=======================================
  Coverage   97.50%   97.50%           
=======================================
  Files          44       44           
  Lines        1960     1962    +2     
=======================================
+ Hits         1911     1913    +2     
  Misses         49       49           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[camposandro]

Looks good!