Fix typo in error message

PiperOrigin-RevId: 276623915
diff --git a/build_tools/python/configure.bzl b/build_tools/python/configure.bzl
index 0e5e7b0..5be4e97 100644
--- a/build_tools/python/configure.bzl
+++ b/build_tools/python/configure.bzl
@@ -81,7 +81,7 @@
         return str(python_bin)  # buildozer: disable=print
 
     fail((
-        "Unable to find python binary (via %s on on PATH %s) " +
+        "Unable to find python binary (via %s on PATH %s) " +
         "Note that PATH resolution on Windows is unreliable. Prefer " +
         "explicit configuration."
     ) % (