Omit the event plot when running the demo on Windows

See #7 and piccolomo/plotext#189 -- this seems to
be an issue somewhere between Plotext itself and Python on Windows; while we
could dive into this and try and solve it, for the purposes of a quick demo
it makes more sense to remove the problematic plot for now.

src/textual_plotext/__main__.py

@@ -20,6 +20,7 @@
 
 from __future__ import annotations
 
+import os
 import random
 from datetime import datetime
 from itertools import chain, cycle
@@ -320,7 +321,7 @@ def compose(self) -> ComposeResult:
             "special",
             [
                 self.ErrorPlot(),
-                self.EventPlot(),
+                *([] if os.name == "nt" else [self.EventPlot()]),
                 self.StreamingDataPlot(),
                 self.MatrixPlot(),
                 self.ConfusionMatrix(),