Fix the build of the ManifestServlet

Author: shs96c

java/client/test/org/openqa/selenium/environment/webserver/build.desc

@@ -31,6 +31,7 @@ java_library(
   ],
   deps = [
     "//javascript:calcdeps",
+    "//java/client/src/org/openqa/selenium/io",
     "//java/client/src/org/openqa/selenium/net",
     "//java/client/test/org/openqa/selenium/testing:util",
     "//java/client/test/org/openqa/selenium/testing/drivers:browser",