Add a nomulus tool command to get allocation tokens

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=239624232

java/google/registry/tools/GtechTool.java

@@ -40,6 +40,7 @@ public final class GtechTool {
       "create_sandbox_tld",
       "delete_domain",
       "generate_dns_report",
+      "get_allocation_token",
       "get_claims_list",
       "get_contact",
       "get_domain",