Prefer re2 over java.util.regex

Java's stock regex implementation doesn't guarantee linear time
complexity which makes it a security liability.
-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=121159875

java/google/registry/tmch/BUILD

@@ -28,9 +28,9 @@ java_library(
         "//third_party/java/jsr305_annotations",
         "//third_party/java/jsr330_inject",
         "//third_party/java/objectify:objectify-v4_1",
+        "//third_party/java/re2j",
         "//third_party/java/servlet/servlet_api",
         "//java/google/registry/config",
-        "//java/google/registry/cron",
         "//java/google/registry/keyring/api",
         "//java/google/registry/model",
         "//java/google/registry/request",

java/google/registry/tmch/LordnLog.java

@@ -20,6 +20,7 @@ import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.Splitter;
 import com.google.common.collect.ImmutableMap;
+import com.google.re2j.Pattern;
 
 import org.joda.time.DateTime;
 
@@ -27,7 +28,6 @@ import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Map.Entry;
-import java.util.regex.Pattern;
 
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;