Fix some issues caught by IntelliJ static code analysis

The most common issues were:
* Arrays.asList() shouldn't be called with a single parameter.
* Broken Javadoc @links.
* Unnecessary casts and type declarations.
* Unnecessary unused variable initializations.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=230994311

java/google/registry/tmch/TmchXmlSignature.java

@@ -126,7 +126,7 @@ public class TmchXmlSignature {
     StringBuilder builder = new StringBuilder();
     builder.append("Signature failed core validation\n");
     boolean sv = signature.getSignatureValue().validate(context);
-    builder.append("Signature validation status: " + sv + "\n");
+    builder.append(String.format("Signature validation status: %s\n", sv));
     for (Reference ref : references) {
       builder.append("references[");
       builder.append(ref.getURI());