Clean up Improved(Input|Output)Stream

Two main changes:

- Replaced getClass().getSimpleName() in the logs with a constructor-given name. Right now what we have is a lot of identical classes with slightly different names so that the logs would be different. With this change - we can later get rid of a lot of these classes and replace them with simple wrappers.

- Removed the "expected" feature. Only Tar uses it - and it can override onClose to do that (that's what it's there for!)

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=202129563

java/google/registry/rde/RydePgpFileOutputStream.java

@@ -51,7 +51,7 @@ public class RydePgpFileOutputStream extends ImprovedOutputStream {
       @WillNotClose OutputStream os,
       DateTime modified,
       String filename) {
-    super(createDelegate(bufferSize, os, modified, filename));
+    super("RydePgpFileOutputStream", createDelegate(bufferSize, os, modified, filename));
   }
 
   private static OutputStream