Refactor/rename refresh all DNS action

I'm moving it out of the scrap folder too because there's nothing else
in there and we do want to retain this indefinitely because it's a useful
tool for performing DNS writer migrations.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=160168902

java/google/registry/tools/server/BUILD

@@ -9,6 +9,7 @@ java_library(
     srcs = glob(["*.java"]),
     deps = [
         "//java/google/registry/config",
+        "//java/google/registry/dns",
         "//java/google/registry/export",
         "//java/google/registry/flows",
         "//java/google/registry/gcs",