Fix display_type() issue for .write attribute in volshell, or other fuctions

Previously, `getattr(volobject, member)` in `display_type()` would incorrectly
retrieve method references (e.g., `.write`) instead of the intended object
addresses, causing an `AttributeError` when `_display_value()` attempted to
access `.vol.offset`.

This commit replaces `getattr(volobject, member)` with `volobject.member(member)`,
ensuring that the correct object address is retrieved instead of method references.

Fixes: #1705

volatility3/cli/volshell/generic.py

@@ -503,7 +503,7 @@ class Volshell(interfaces.plugins.PluginInterface):
                 if isinstance(volobject, interfaces.objects.ObjectInterface):
                     # We're an instance, so also display the data
                     try:
-                        value = self._display_value(getattr(volobject, member))
+                        value = self._display_value(volobject.member(member))
                     except exceptions.InvalidAddressException:
                         value = self._display_value(renderers.NotAvailableValue())
                     print(