[release-branch.go1.15-security] go1.15.5

Change-Id: Id3b116c0f54c2131111bc8afacb8d81d06f96461
Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/901407
Reviewed-by: Katie Hockman <katiehockman@google.com>
diff --git a/VERSION b/VERSION
index b0378bd..d4bbebb 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-go1.15.4
\ No newline at end of file
+go1.15.5
\ No newline at end of file