Add missing slf4j dependencies in BUILD file

slf4j dependencies were not included in the BUILD file (I43e6cf797cc)
which cause the Bazel build to fail when attempting to run the tests.

Change-Id: Ie5c8bbb80625453a066e29f92660da7b0e5c8674
diff --git a/javatests/com/google/gerrit/elasticsearch/BUILD b/javatests/com/google/gerrit/elasticsearch/BUILD
index b5378a4..8bc738f 100644
--- a/javatests/com/google/gerrit/elasticsearch/BUILD
+++ b/javatests/com/google/gerrit/elasticsearch/BUILD
@@ -18,6 +18,7 @@
         "//lib/guice",
         "//lib/httpcomponents:httpcore",
         "//lib/jgit/org.eclipse.jgit:jgit",
+        "//lib/log:api",
         "//lib/testcontainers",
         "//lib/testcontainers:testcontainers-elasticsearch",
     ],