Fix python Value equality (#817)

## Usage and product changes
Fixes the implementation of `__eq__` in `_Value` to use `try_get_value_type` instead of the non-existent `get_value_type`

Author: krishnangovindraj

python/typedb/concept/value/value.py

@@ -115,7 +115,7 @@ def __str__(self):
     def __eq__(self, other):
         if other is self:
             return True
-        if not other or type(self) is not type(other) or self.get_value_type() != other.get_value_type():
+        if not other or type(self) is not type(other) or self.try_get_value_type() != other.try_get_value_type():
             return False
         return self.get() == other.get()