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/util/PosixTarHeader.java

@@ -105,7 +105,7 @@ public final class PosixTarHeader {
     DIRECTORY,
 
     /** This indicates we read a file from an archive with an unsupported type. */
-    UNSUPPORTED;
+    UNSUPPORTED
   }
 
   public static final int HEADER_LENGTH = 512;