Remove redundant inputXml log in EPP flows

Currently the input XML to an EPP flow is logged twice, once
in FlowRunner and once in FlowReporter.

The log by FlowReporter was used by reporting but this is no
longer the case.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=200057153

java/google/registry/flows/FlowReporter.java

@@ -15,8 +15,6 @@
 package google.registry.flows;
 
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
-import static com.google.common.io.BaseEncoding.base64;
-import static google.registry.xml.XmlTransformer.prettyPrint;
 import static java.util.Collections.EMPTY_LIST;
 
 import com.google.common.base.Ascii;
@@ -37,13 +35,6 @@ import org.json.simple.JSONValue;
 /** Reporter used by {@link FlowRunner} to record flow execution data for reporting. */
 public class FlowReporter {
 
-  /**
-   * Log signature for recording flow EPP input data.
-   *
-   * <p><b>WARNING:<b/> DO NOT CHANGE this value unless you want to break reporting.
-   */
-  private static final String EPPINPUT_LOG_SIGNATURE = "FLOW-LOG-SIGNATURE-EPPINPUT";
-
   /**
    * Log signature for recording flow metadata (anything beyond or derived from the raw EPP input).
    *
@@ -62,15 +53,6 @@ public class FlowReporter {
 
   /** Records information about the current flow execution in the GAE request logs. */
   public void recordToLogs() {
-    // WARNING: These log statements are parsed by reporting pipelines - be careful when changing.
-    // It should be safe to add new keys, but be very cautious in changing existing keys.
-    logger.atInfo().log(
-        "%s: %s",
-        EPPINPUT_LOG_SIGNATURE,
-        JSONValue.toJSONString(
-            ImmutableMap.<String, Object>of(
-                "xml", prettyPrint(inputXmlBytes),
-                "xmlBytes", base64().encode(inputXmlBytes))));
     // Explicitly log flow metadata separately from the EPP XML itself so that it stays compact
     // enough to be sure to fit in a single log entry (the XML part in rare cases could be long
     // enough to overflow into multiple log entries, breaking routine parsing of the JSON format).