Catch ImportError instead of Exception

`distutils.version` is deprecated. When using the `FigureWidget` in unit tests with `pytest` where warnings are promoted to errors, the warning becomes an error and the error message is that we have to install `ipywidgets>=7.0.0`, even if `ipywidgets` is installed in the current environment.

Author: nvaytet

packages/python/plotly/plotly/graph_objects/__init__.py

@@ -273,7 +273,7 @@
             from ..graph_objs._figurewidget import FigureWidget
         else:
             raise ImportError()
-    except Exception:
+    except ImportError:
         from ..missing_ipywidgets import FigureWidget
 else:
     __all__.append("FigureWidget")
@@ -291,7 +291,7 @@ def __getattr__(import_name):
                     return FigureWidget
                 else:
                     raise ImportError()
-            except Exception:
+            except ImportError:
                 from ..missing_ipywidgets import FigureWidget
 
                 return FigureWidget