Make javadoc <p> style guide compliant

This led to confusion for an open source contributor about how to format
code. We don't want to be like, "do as I say, not as I do."

https://google.github.io/styleguide/javaguide.html#s7.1.2-javadoc-paragraphs
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=122589700

java/google/registry/model/domain/secdns/SecDnsCreateExtension.java

@@ -32,8 +32,9 @@ import javax.xml.bind.annotation.XmlType;
 public class SecDnsCreateExtension extends ImmutableObject implements CommandExtension {
   /**
    * Time in seconds until the signature should expire.
-   * <p>
-   * We do not support expirations, but we need this field to be able to return appropriate errors.
+   *
+   * <p>We do not support expirations, but we need this field to be able to return appropriate
+   * errors.
    */
   Long maxSigLife;