Migrate to internal FormattingLogger in preparation of migration to Flogger

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=197744904

java/google/registry/module/tools/BUILD

@@ -8,6 +8,7 @@ java_library(
     name = "tools",
     srcs = glob(["*.java"]),
     deps = [
+        "//java/com/google/common/logging:formatting_logger",
         "//java/google/registry/backup",
         "//java/google/registry/config",
         "//java/google/registry/dns",

java/google/registry/module/tools/ToolsServlet.java

@@ -14,7 +14,7 @@
 
 package google.registry.module.tools;
 
-import google.registry.util.FormattingLogger;
+import com.google.common.logging.FormattingLogger;
 import java.io.IOException;
 import java.security.Security;
 import javax.servlet.http.HttpServlet;