Adding escape call to sitecustomize sub call.

Fixes auto-instrumentation not producing spans on Windows. See the
following issue:
https://github.com/open-telemetry/opentelemetry-python/issues/2703

Author: jeremydvoss

CHANGELOG.md

@@ -7,6 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased](https://github.com/open-telemetry/opentelemetry-python/compare/v1.12.0rc1-0.31b0...HEAD)
 
+- Adding escape call to fix [auto-instrumentation not producing spans on Windows](https://github.com/open-telemetry/opentelemetry-python/issues/2703).
+  ([#<PR>](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/<PR>))
+
 ## [1.12.0rc1-0.31b0](https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.12.0rc1-0.31b0) - 2022-05-17
 
 

opentelemetry-instrumentation/src/opentelemetry/instrumentation/auto_instrumentation/sitecustomize.py

@@ -15,7 +15,7 @@
 from logging import getLogger
 from os import environ
 from os.path import abspath, dirname, pathsep
-from re import sub
+from re import sub, escape
 
 from pkg_resources import iter_entry_points
 
@@ -112,7 +112,7 @@ def _load_configurators():
 def initialize():
     # prevents auto-instrumentation of subprocesses if code execs another python process
     environ["PYTHONPATH"] = sub(
-        rf"{dirname(abspath(__file__))}{pathsep}?",
+        escape(rf"{dirname(abspath(__file__))}{pathsep}?"),
         "",
         environ["PYTHONPATH"],
     )