TEST: Switch to single quotes for expected magic errors

Author: effigies

nibabel/tests/test_nifti1.py

@@ -251,7 +251,7 @@ def test_magic_offset_checks(self):
         fhdr, message, raiser = self.log_chk(hdr, 45)
         assert fhdr['magic'] == b'ooh'
         assert (
-            message == 'magic string "ooh" is not valid; '
+            message == "magic string 'ooh' is not valid; "
             'leaving as is, but future errors are likely'
         )
         # For pairs, any offset is OK, but should be divisible by 16

nibabel/tests/test_scripts.py

@@ -228,7 +228,7 @@ def test_nib_nifti_dx():
     expected = f"""Picky header check output for "{dirty_hdr}"
 
 pixdim[0] (qfac) should be 1 (default) or -1
-magic string "" is not valid
+magic string '' is not valid
 sform_code 11776 not valid"""
     # Split strings to remove line endings
     assert stdout == expected