Python: Add test-cases for BuiltinFunction and BuiltinMethod

Author: RasmusWL

python/ql/test/library-tests/PointsTo/calls/Argument.expected

@@ -13,3 +13,6 @@
 | 25 | 1 | ControlFlowNode for z | Function C.n |
 | 33 | 0 | ControlFlowNode for IntegerLiteral | Function D.foo |
 | 34 | 0 | ControlFlowNode for IntegerLiteral | Function D.foo |
+| 37 | 0 | ControlFlowNode for l | builtin method append |
+| 37 | 1 | ControlFlowNode for IntegerLiteral | builtin method append |
+| 38 | 0 | ControlFlowNode for l | Builtin-function len |

python/ql/test/library-tests/PointsTo/calls/CallPointsTo.expected

@@ -8,3 +8,5 @@
 | 33 | ControlFlowNode for Attribute() | Function D.foo |
 | 34 | ControlFlowNode for Attribute() | Function D.foo |
 | 34 | ControlFlowNode for D() | class D |
+| 37 | ControlFlowNode for Attribute() | Method(builtin method append, List) |
+| 38 | ControlFlowNode for len() | Builtin-function len |

python/ql/test/library-tests/PointsTo/calls/GetACall.expected

@@ -10,3 +10,6 @@
 | 33 | ControlFlowNode for Attribute() | Function D.foo |
 | 34 | ControlFlowNode for Attribute() | Function D.foo |
 | 34 | ControlFlowNode for D() | class D |
+| 37 | ControlFlowNode for Attribute() | Method(builtin method append, List) |
+| 37 | ControlFlowNode for Attribute() | builtin method append |
+| 38 | ControlFlowNode for len() | Builtin-function len |

python/ql/test/library-tests/PointsTo/calls/test.py

@@ -32,3 +32,7 @@ def foo(arg):
 
 D.foo(1)
 D().foo(2)
+
+l = [1,2,3]
+l.append(4)
+len(l)