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

javatests/google/registry/util/CidrAddressBlockTest.java

@@ -67,8 +67,6 @@ public class CidrAddressBlockTest extends TestCase {
     assertEquals(32, b1.getNetmask());
     b1 = new CidrAddressBlock("2001:db8::1");
     assertEquals(128, b1.getNetmask());
-    b1 = new CidrAddressBlock("3ffe::/16");
-
     b1 = new CidrAddressBlock(InetAddresses.forString("5ffe::1"));
     assertEquals(128, b1.getNetmask());
     assertEquals("5ffe:0:0:0:0:0:0:1", b1.getIp());