Remove final on @ParametersDelegate field

Compile-time constant inlining may interfere with JCommander's processing if a field is made final - @ParametersDelegate fields are particularly misleading.  Remove the one instance of that and add warning comments elsewhere.  See

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=136469351

java/google/registry/tools/BigqueryCommand.java

@@ -21,6 +21,7 @@ import google.registry.bigquery.BigqueryConnection;
 abstract class BigqueryCommand implements Command {
 
   /** Parameter delegate for encapsulating flags needed to set up the {@link BigqueryConnection}. */
+  // Do not make this final - compile-time constant inlining may interfere with JCommander.
   @ParametersDelegate
   private BigqueryParameters bigqueryParameters = new BigqueryParameters();
 

java/google/registry/tools/RegistrarActivityReportCommand.java

@@ -36,8 +36,9 @@ import org.joda.time.format.DateTimeFormatter;
 @Parameters(separators = " =", commandDescription = "Generates a registrar activity report.")
 final class RegistrarActivityReportCommand implements Command {
 
+  // Do not make this final - compile-time constant inlining may interfere with JCommander.
   @ParametersDelegate
-  private final BigqueryParameters bigqueryParameters = new BigqueryParameters();
+  private BigqueryParameters bigqueryParameters = new BigqueryParameters();
 
   @Parameter(
       names = {"-t", "--tld"},

java/google/registry/tools/RegistryCli.java

@@ -42,9 +42,11 @@ final class RegistryCli {
       description = "Sets the default environment to run the command.")
   private RegistryToolEnvironment environment = RegistryToolEnvironment.PRODUCTION;
 
+  // Do not make this final - compile-time constant inlining may interfere with JCommander.
   @ParametersDelegate
   private AppEngineConnection connection = new AppEngineConnection();
 
+  // Do not make this final - compile-time constant inlining may interfere with JCommander.
   @ParametersDelegate
   private LoggingParameters loggingParams = new LoggingParameters();