fix: read-only toolchain lib folder under Windows

We already set the lib folder to read-only on macOS and Linux, so we
need to set on Windows as well. This should solve the problem of .pyc
files changing a busting the cache.

Signed-off-by: Thulio Ferraz Assis <3149049+f0rmiga@users.noreply.github.com>

python/repositories.bzl

diff --git a/python/repositories.bzl b/python/repositories.bzl
index 687388c..7518861 100644
--- a/python/repositories.bzl
+++ b/python/repositories.bzl
@@ -102,6 +102,10 @@
         exec_result = rctx.execute(["chmod", "-R", "ugo-w", "lib"])
         if exec_result.return_code:
             fail(exec_result.stderr)
+    else:
+        exec_result = rctx.execute(["attrib", "+r", "%cd%\\lib\\*.*", "/s", "/d"])
+        if exec_result.return_code:
+            fail(exec_result.stderr)
 
     python_bin = "python.exe" if ("windows" in platform) else "bin/python3"