Make LenientFormatStringValidation a warning

PiperOrigin-RevId: 502649182
Change-Id: Id44a9e06432f937438f977c652cd19a2014ad067

toolchains/default_java_toolchain.bzl

diff --git a/toolchains/default_java_toolchain.bzl b/toolchains/default_java_toolchain.bzl
index 9b7ffb9..9c2b1fc 100644
--- a/toolchains/default_java_toolchain.bzl
+++ b/toolchains/default_java_toolchain.bzl
@@ -57,6 +57,7 @@
     # https://github.com/bazelbuild/bazel/issues/16996
     "-Xep:IgnoredPureGetter:OFF",
     "-Xep:EmptyTopLevelDeclaration:OFF",
+    "-Xep:LenientFormatStringValidation:OFF",
 ]
 
 # Default java_toolchain parameters