Stop exporting EPP flow metrics to BigQuery

These are simply too costly in their current form now that we are handling double-digit QPS, so at a minimum we'd want to refactor these for batched exports using a background thread (like how Stackdriver metrics work). However, upon further review, that work isn't worth doing if this BigQuery table isn't actually being used for anything, and it seems that we aren't using it anymore given that ICANN transaction reporting no longer requires it.

So the simplest thing to do is simply to get rid of this entirely, and just use a combination of Stackdriver metrics and App Engine logs. The eppMetrics BigQuery table is ~1.2 billion rows and takes up 223 GB, so that's not an insignificant GCP billings saving if we can delete it.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=215905466

javatests/google/registry/flows/EppLifecycleDomainTest.java

@@ -440,8 +440,6 @@ public class EppLifecycleDomainTest extends EppTestCase {
         .and()
         .hasCommandName("HostUpdate")
         .and()
-        .hasEppTarget("ns3.fakesite.example")
-        .and()
         .hasStatus(SUCCESS);
     // Delete the fakesite.example domain (which should succeed since it no longer has subords).
     assertThatCommand("domain_delete.xml", ImmutableMap.of("DOMAIN", "fakesite.example"))
@@ -454,8 +452,6 @@ public class EppLifecycleDomainTest extends EppTestCase {
         .and()
         .hasCommandName("DomainDelete")
         .and()
-        .hasEppTarget("fakesite.example")
-        .and()
         .hasStatus(SUCCESS_WITH_ACTION_PENDING);
     // Check info on the renamed host and verify that it's still around and wasn't deleted.
     assertThatCommand("host_info_ns9000_example.xml")
@@ -466,8 +462,6 @@ public class EppLifecycleDomainTest extends EppTestCase {
         .and()
         .hasCommandName("HostInfo")
         .and()
-        .hasEppTarget("ns9000.example.external")
-        .and()
         .hasStatus(SUCCESS);
     assertThatLogoutSucceeds();
     assertThat(getRecordedEppMetric())
@@ -575,8 +569,6 @@ public class EppLifecycleDomainTest extends EppTestCase {
         .and()
         .hasCommandName("DomainCheck")
         .and()
-        .hasEppTarget("rich.example")
-        .and()
         .hasTld("example")
         .and()
         .hasStatus(SUCCESS);