fix: fix import of lex and yacc depending on astropy version

these modules's location changed in astropy version 4.3

astroquery/simbad/utils.py

@@ -1,10 +1,16 @@
 """Contains utility functions to support legacy Simbad interface."""
 
 from collections import deque
+from packaging import version
 import re
 
+from astropy import __version__ as astropy_version
+
 from astropy.coordinates import SkyCoord, Angle
-from astropy.utils.parsing import lex, yacc
+if version.parse(astropy_version) >= version.parse("4.3"): 
+    from astropy.utils.parsing import lex, yacc
+else:
+    from astropy.extern.ply import lex, yacc
 from astropy.utils import classproperty