tools/javadoc.bzl: Migrate deprecated JavaInfo API usage

In If22d6e870b the deprecated JavaInfo usages were updated, but one
place was missed to be updated.

Change-Id: I113b07c51a1acc64f3d32d970385256f7ef1fb43
diff --git a/tools/javadoc.bzl b/tools/javadoc.bzl
index 4799254..a95989d 100644
--- a/tools/javadoc.bzl
+++ b/tools/javadoc.bzl
@@ -17,7 +17,7 @@
 def _impl(ctx):
     zip_output = ctx.outputs.zip
 
-    transitive_jars = depset(transitive = [j[JavaInfo].transitive_deps for j in ctx.attr.libs])
+    transitive_jars = depset(transitive = [j[JavaInfo].transitive_compile_time_jars for j in ctx.attr.libs])
     # TODO(davido): Remove list to depset conversion on source_jars, when this issue is fixed:
     # https://github.com/bazelbuild/bazel/issues/4221
     source_jars = depset(transitive = [depset(j[JavaInfo].source_jars) for j in ctx.attr.libs])