Fix build error by adding testonly=1 to eclipse BUILD file

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=138652263

java/google/registry/eclipse/BUILD

@@ -18,6 +18,7 @@ java_binary(
 
 java_binary(
     name = "registry_deps",
+    testonly = 1,
     create_executable = 0,
     runtime_deps = [
         "//java/com/google/common/testing",