BUG: Make Period and int comparable

Author: Licht-T

pandas/_libs/period.pyx

@@ -712,6 +712,10 @@ cdef class _Period(object):
             return PyObject_RichCompareBool(self.ordinal, other.ordinal, op)
         elif other is NaT:
             return _nat_scalar_rules[op]
+        elif util.is_integer_object(other):
+            return PyObject_RichCompareBool(self.ordinal,
+                                            other * self.freq.n,
+                                            op)
         # index/series like
         elif hasattr(other, '_typ'):
             return NotImplemented