Skip hdf5 tests if hdf5 isn't installed.

Author: erykoff

tests/test_io_hdf5.py

@@ -11,6 +11,10 @@
 import healsparse
 
 
+if not healsparse.io_map_hdf5.use_hdf5:
+    pytest.skip("Skipping hdf5 tests", allow_module_level=True)
+
+
 class Hdf5IoTestCase(unittest.TestCase):
     def test_hdf5_writeread(self):
         """