[FEM] Avoid writing parse cache file to non-writable location

Creating the parsetab.py cache file in the same location as the tokrules
file will fail when FreeCAD is installed system wide.

Caching provides hardly any benefit here, as it only takes milliseconds,
and may even be negated by the additional required filesystem operations.

The debug output (parser.out) does not provide any useful information
for a regular FreeCAD user.

Fixes (part of) #6315.

src/Mod/Fem/femtools/tokrules.py

@@ -153,4 +153,4 @@ def p_error(p):
 
 
 import ply.yacc as yacc
-yacc.yacc()
+yacc.yacc(debug=False, write_tables=False)