Add Dataflow path to generate overall monthly invoice

This forks off the results of the billing_events query from Bigquery and generates the overall invoice for the month.

This also turns the ad hoc beam binary into a proper Nomulus command, allowing us to @Inject from the RegsistryToolComponent and thus template the BillingEvent Bigquery query.

Next steps:
- Add the beam package to the open source build
  - That will likely require updates to the open source jars, since I'm using features from 2.2.0 which was only just released.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178798943

java/google/registry/tools/RegistryTool.java

@@ -55,6 +55,7 @@ public final class RegistryTool {
           .put("delete_premium_list", DeletePremiumListCommand.class)
           .put("delete_reserved_list", DeleteReservedListCommand.class)
           .put("delete_tld", DeleteTldCommand.class)
+          .put("deploy_invoicing_pipeline", DeployInvoicingPipelineCommand.class)
           .put("domain_application_info", DomainApplicationInfoCommand.class)
           .put("domain_check", DomainCheckCommand.class)
           .put("domain_check_claims", DomainCheckClaimsCommand.class)