Map /_dr/task/uploadBsaUnavailableNames in BSA service's web.xml (#2276)

This should have been part of PR #2265 but we all missed it.

Also adds a couple of useful logging statements.

core/src/main/java/google/registry/bsa/UploadBsaUnavailableDomainsAction.java

@@ -187,6 +187,8 @@ public class UploadBsaUnavailableDomainsAction implements Runnable {
             .filter(tld -> isEnrolledWithBsa(tld, runTime))
             .collect(toImmutableSet());
 
+    logger.atInfo().log("Getting unavailable domains in TLDs: %s ...", bsaEnabledTlds);
+
     ImmutableSortedSet.Builder<String> unavailableDomains =
         new ImmutableSortedSet.Builder<>(Ordering.natural());
     for (Tld tld : bsaEnabledTlds) {
@@ -211,7 +213,9 @@ public class UploadBsaUnavailableDomainsAction implements Runnable {
                 "tlds", bsaEnabledTlds.stream().map(Tld::getTldStr).collect(toImmutableSet()))
             .setParameter("now", runTime)
             .getResultList());
-    return unavailableDomains.build();
+    ImmutableSortedSet<String> result = unavailableDomains.build();
+    logger.atInfo().log("Found %d total unavailable domains.", result.size());
+    return result;
   }
 
   private static String toDomain(String domainLabel, Tld tld) {

core/src/main/java/google/registry/env/common/bsa/WEB-INF/web.xml

@@ -25,6 +25,12 @@
     <url-pattern>/_dr/task/bsaRefresh</url-pattern>
   </servlet-mapping>
 
+  <!-- Upload unavailable domains to BSA action -->
+  <servlet-mapping>
+    <servlet-name>bsa-servlet</servlet-name>
+    <url-pattern>/_dr/task/uploadBsaUnavailableNames</url-pattern>
+  </servlet-mapping>
+
   <!-- Security config -->
   <security-constraint>
     <web-resource-collection>