Remove @Parameter from RdeStagingReducer

The "lenient" bit must be the same between RdeStagingMapper and
RdeStagingReducer, but this is hidden by the Reducer receiving the bit in a
completely different way than the mapper.

There are 2 ways to do this:
- add a "setLenient" function to RdeStagingReducer that we MUST call, or else
  get a runtime error. This is the simplest solution
- have a RdeStagingReducerBuilder you can inject, and that requires the
  "lenient" value to actually build the RdeStagingReducer. This prevents bugs
  at compile-time but is "more complicated"

I'm going with the second one here, but feel free to ask for the first one.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=229423590

javatests/google/registry/rde/RdeStagingActionTest.java

@@ -131,14 +131,13 @@ public class RdeStagingActionTest extends MapreduceTestCase<RdeStagingAction> {
     action.clock = clock;
     action.mrRunner = makeDefaultRunner();
     action.lenient = false;
-    action.reducer = new RdeStagingReducer(
-        new TaskQueueUtils(new Retrier(new SystemSleeper(), 1)), // taskQueueUtils
-        new FakeLockHandler(true),
-        0, // gcsBufferSize
-        "rde-bucket", // bucket
-        Duration.standardHours(1), // lockTimeout
-        PgpHelper.convertPublicKeyToBytes(encryptKey), // stagingKeyBytes
-        false); // lenient
+    action.reducerFactory = new RdeStagingReducer.Factory();
+    action.reducerFactory.taskQueueUtils = new TaskQueueUtils(new Retrier(new SystemSleeper(), 1));
+    action.reducerFactory.lockHandler = new FakeLockHandler(true);
+    action.reducerFactory.gcsBufferSize = 0;
+    action.reducerFactory.bucket = "rde-bucket";
+    action.reducerFactory.lockTimeout = Duration.standardHours(1);
+    action.reducerFactory.stagingKeyBytes = PgpHelper.convertPublicKeyToBytes(encryptKey);
     action.pendingDepositChecker = new PendingDepositChecker();
     action.pendingDepositChecker.brdaDayOfWeek = DateTimeConstants.TUESDAY;
     action.pendingDepositChecker.brdaInterval = Duration.standardDays(7);