pySim.esim.saip: Add ProfileElementAKA constructor + methods

This helps us to construct an akaParameter PE from scratch.

Change-Id: I4cc42c98bf82aec085ab7f48aea4ff7efa0eae9e

tests/test_esim_saip.py

@@ -66,7 +66,7 @@ class SaipTest(unittest.TestCase):
     def test_constructor_encode(self):
         """Test that DER-encoding of PE created by "empty" constructor works without raising exception."""
         for cls in [ProfileElementMF, ProfileElementPuk, ProfileElementPin, ProfileElementTelecom,
-                    ProfileElementUSIM, ProfileElementISIM]:
+                    ProfileElementUSIM, ProfileElementISIM, ProfileElementAKA]:
             with self.subTest(cls.__name__):
                 pes = ProfileElementSequence()
                 inst = cls()