Remove reference to accounts_byemail cache

Gerrit does not have an accounts_byemail cache anymore
since v2.15.

There is no value in trying to warm an inexistent cache other
than making this script failing to load.

Change-Id: Ib3575492a5ae9b09620d7b5541541583f47267b9
diff --git a/admin/warm-cache-1.0.groovy b/admin/warm-cache-1.0.groovy
index 5ba12c2..eb1df2c 100644
--- a/admin/warm-cache-1.0.groovy
+++ b/admin/warm-cache-1.0.groovy
@@ -117,9 +117,6 @@
   AccountCache cache
 
   @Inject
-  AccountByEmailCache cacheByEmail
-
-  @Inject
   Provider<ReviewDb> db
 
   public void run() {
@@ -130,9 +127,6 @@
 
     for (account in allAccounts) {
       cache.get(account.accountId)
-      if (account.preferredEmail != null) {
-        cacheByEmail.get(account.preferredEmail)
-      }
       loaded++
       if (loaded%1000==0) {
         println "$loaded accounts"