Bazel: Add fixes for --incompatible_load_java_rules_from_bzl

Change-Id: I5c37e69dd371c3e24a7981f632bd3e58741679d3

lib/slf4j/BUILD

diff --git a/lib/slf4j/BUILD b/lib/slf4j/BUILD
index b619aaa..2719aa8 100644
--- a/lib/slf4j/BUILD
+++ b/lib/slf4j/BUILD
@@ -1,3 +1,5 @@
+load("@rules_java//java:defs.bzl", "java_library")
+
 package(
     default_visibility = ["//visibility:public"],
 )