Document exit code 38 as a BES error

Resolves #13969.

This way users can know they can ignore this error in scripts.

Closes #20756.

PiperOrigin-RevId: 596593376
Change-Id: Idf5f9ec3dc03f87cc431c299a0f920b1cc0d884e
diff --git a/site/en/run/scripts.md b/site/en/run/scripts.md
index 86932b2..e7e7282 100644
--- a/site/en/run/scripts.md
+++ b/site/en/run/scripts.md
@@ -56,10 +56,10 @@
 -   `35` - Reserved for Google-internal use.
 -   `36` - Local Environmental Issue, suspected permanent.
 -   `37` - Unhandled Exception / Internal Bazel Error.
--   `38` - Reserved for Google-internal use.
+-   `38` - Transient error publishing results to the Build Event Service.
 -   `39` - Blobs required by Bazel are evicted from Remote Cache.
 -   `41-44` - Reserved for Google-internal use.
--   `45` - Error publishing results to the Build Event Service.
+-   `45` - Persistent error publishing results to the Build Event Service.
 -   `47` - Reserved for Google-internal use.
 -   `49` - Reserved for Google-internal use.