Issue #23731: Implement PEP 488.

The concept of .pyo files no longer exists. Now .pyc files have an
optional `opt-` tag which specifies if any extra optimizations beyond
the peepholer were applied.
diff --git a/Lib/trace.py b/Lib/trace.py
index 41eff26..f108266 100755
--- a/Lib/trace.py
+++ b/Lib/trace.py
@@ -305,7 +305,7 @@
             if self.is_ignored_filename(filename):
                 continue
 
-            if filename.endswith((".pyc", ".pyo")):
+            if filename.endswith(".pyc"):
                 filename = filename[:-1]
 
             if coverdir is None: