Remove invalid test.

This one I'd added thinking I ought to block store from using
a const var target. But since I figured it's better to just
restrict adding vars to the circuit that are const (and leave
the decision of whether or not a const var can be an l-value
till later), this test no longer makes sense.

test/python/circuit/test_store.py

@@ -240,14 +240,6 @@ def test_rejects_non_lvalue(self):
         with self.assertRaisesRegex(CircuitError, "not an l-value"):
             qc.store(not_an_lvalue, expr.lift(False))
 
-    def test_rejects_const_lvalue(self):
-        """At least for now, lvalue expressions with a const type are not
-        permitted in calls to qc.store."""
-        a = expr.Var.new("a", types.Bool(const=True))
-        qc = QuantumCircuit()
-        with self.assertRaisesRegex(CircuitError, "const variables.*not supported"):
-            qc.store(a, expr.lift(False, try_const=True))
-
     def test_rejects_explicit_cast(self):
         lvalue = expr.Var.new("a", types.Uint(16))
         rvalue = expr.Var.new("b", types.Uint(8))