Add "pubapi" App Engine service for check API, WHOIS, and RDAP

The migration plan is as follows:
1. This CL, which adds the new "pubapi" service that serves the check API, WHOIS, and RDAP.
2a. Update our public facing sites to switch over to use the new service.
2b. (either order) Rewrite the check API to remove dependencies on flows.
3. ... eventually, once the frontend service is no longer being hit by this traffic, remove its handling of these public endpoints.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=197716346

java/google/registry/module/pubapi/PubApiRequestComponent.java

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+// Copyright 2018 The Nomulus Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package google.registry.module.pubapi;
+
+import dagger.Module;
+import dagger.Subcomponent;
+import google.registry.dns.DnsModule;
+import google.registry.flows.CheckApiAction;
+import google.registry.flows.CheckApiAction.CheckApiModule;
+import google.registry.flows.FlowComponent;
+import google.registry.flows.TlsCredentials.EppTlsModule;
+import google.registry.monitoring.whitebox.WhiteboxModule;
+import google.registry.rdap.RdapAutnumAction;
+import google.registry.rdap.RdapDomainAction;
+import google.registry.rdap.RdapDomainSearchAction;
+import google.registry.rdap.RdapEntityAction;
+import google.registry.rdap.RdapEntitySearchAction;
+import google.registry.rdap.RdapHelpAction;
+import google.registry.rdap.RdapIpAction;
+import google.registry.rdap.RdapModule;
+import google.registry.rdap.RdapNameserverAction;
+import google.registry.rdap.RdapNameserverSearchAction;
+import google.registry.request.RequestComponentBuilder;
+import google.registry.request.RequestModule;
+import google.registry.request.RequestScope;
+import google.registry.whois.WhoisAction;
+import google.registry.whois.WhoisHttpAction;
+import google.registry.whois.WhoisModule;
+
+/** Dagger component with per-request lifetime for "pubapi" App Engine module. */
+@RequestScope
+@Subcomponent(
+    modules = {
+        CheckApiModule.class,
+        DnsModule.class,
+        EppTlsModule.class,
+        RdapModule.class,
+        RequestModule.class,
+        WhiteboxModule.class,
+        WhoisModule.class,
+    })
+interface PubApiRequestComponent {
+  CheckApiAction checkApiAction();
+  // TODO(b/79692981): Remove flow-related includes once check API is rewritten to not wrap flow.
+  FlowComponent.Builder flowComponentBuilder();
+  RdapAutnumAction rdapAutnumAction();
+  RdapDomainAction rdapDomainAction();
+  RdapDomainSearchAction rdapDomainSearchAction();
+  RdapEntityAction rdapEntityAction();
+  RdapEntitySearchAction rdapEntitySearchAction();
+  RdapHelpAction rdapHelpAction();
+  RdapIpAction rdapDefaultAction();
+  RdapNameserverAction rdapNameserverAction();
+  RdapNameserverSearchAction rdapNameserverSearchAction();
+  WhoisHttpAction whoisHttpAction();
+  WhoisAction whoisAction();
+
+  @Subcomponent.Builder
+  abstract class Builder implements RequestComponentBuilder<PubApiRequestComponent> {
+    @Override public abstract Builder requestModule(RequestModule requestModule);
+    @Override public abstract PubApiRequestComponent build();
+  }
+
+  @Module(subcomponents = PubApiRequestComponent.class)
+  class PubApiRequestComponentModule {}
+}