Fix some statically detected code issues

This includes: unnecessary semicolons, suppress warnings, switch statements, final/private qualifiers, Optional wrapping, conditionals, both inline and non-inline variables, ternaries, Collection putAll() calls, StringBuilders, and throws declarations.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=244182539

java/google/registry/rde/RydePgpSigningOutputStream.java

@@ -96,7 +96,6 @@ public class RydePgpSigningOutputStream extends ImprovedOutputStream {
    * googler who was also uncertain about the precise reason why it's needed.
    */
   private static void addUserInfoToSignature(PGPPublicKey publicKey, PGPSignatureGenerator signer) {
-    @SuppressWarnings("unchecked") // safe by specification.
     Iterator<String> uidIter = publicKey.getUserIDs();
     if (uidIter.hasNext()) {
       PGPSignatureSubpacketGenerator spg = new PGPSignatureSubpacketGenerator();