Ensure use of float64 when calling radec2pix

[gitosaurus]

Change Description

In the function healpix_shim.py.radec2pix, convert ra and dec to 64-bit floating point before attempting to call cdshealpix.lonlat_to_healpix, which raises a TypeError if it receives 32-bit floating point.

Closes astronomy-commons/hats-import#458 .

Have verified this fix both with an updated unit test, and also by exercising the code in a separate build of a margin cache, which produced another instance of the above issue. This time, using a local checkout of this fix, the mapping phase continued past 5% without any instance of the error (which arose much earlier than the 5% mark before).

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Code Quality

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Bug Fix Checklist

• My fix includes a new test that breaks as a result of the bug (if possible)
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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.24%. Comparing base (171b901) to head (c61ba25).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #447   +/-   ##
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  Coverage   93.24%   93.24%           
=======================================
  Files          47       47           
  Lines        2012     2012           
=======================================
  Hits         1876     1876           
  Misses        136      136           

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[github-actions]

Before [171b901]	After [fb03a6c]	Ratio	Benchmark (Parameter)
18.9±0.3ms	19.2±0.4ms	1.02	benchmarks.MetadataSuite.time_load_partition_info_order6
75.6±0.2ms	76.3±0.4ms	1.01	benchmarks.MetadataSuite.time_load_partition_info_order7
74.8±0.1ms	75.9±0.5ms	1.01	benchmarks.MetadataSuite.time_load_partition_join_info
13.2±0.4ms	13.3±0.3ms	1.01	benchmarks.Suite.time_inner_pixel_alignment
364±3ms	369±1ms	1.01	benchmarks.Suite.time_outer_pixel_alignment
114±0.3ms	113±0.5ms	1	benchmarks.time_test_alignment_even_sky
41.7±0.4ms	41.5±0.5ms	0.99	benchmarks.Suite.time_pixel_tree_creation
1.06±0.04ms	1.03±0.04ms	0.98	benchmarks.time_test_cone_filter_multiple_order

Click here to view all benchmarks.

[nevencaplar]

Looks good to me!