frappy.client: catch all errors in handleError callback

put try/execpt around handleError callback

Change-Id: I3d97f085556665189da848e52a7148248f55eb0e
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/34955
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

frappy/client/__init__.py

@@ -481,7 +481,10 @@ class SecopClient(ProxyClient):
                                 continue
                 except Exception as e:
                     e.args = (f'error handling SECoP message {reply!r}: {e}',)
-                    self.callback(None, 'handleError',  e)
+                    try:
+                        self.callback(None, 'handleError',  e)
+                    except Exception:
+                        pass
                     continue
                 try:
                     key = action, ident