Rename DNL and SMDRL "login" to "loginAndPassword"

They are passed around in the format username:password, whereas just saying
"login" implies it's just a username and not necessarily also a secret
password. Putting password in the variable name makes it obvious what this is
and reduces the likelihood of anyone ever logging it or otherwise using it
inappropriately.

Note that this does not require data migrations as the actual key used to store
the data in KMS remains unchanged.

This is a follow-up to []

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=231253964

java/google/registry/tools/params/KeyringKeyName.java

@@ -26,9 +26,9 @@ public enum KeyringKeyName {
   BRDA_SIGNING_PUBLIC_KEY,
   ICANN_REPORTING_PASSWORD,
   JSON_CREDENTIAL,
-  MARKSDB_DNL_LOGIN,
+  MARKSDB_DNL_LOGIN_AND_PASSWORD,
   MARKSDB_LORDN_PASSWORD,
-  MARKSDB_SMDRL_LOGIN,
+  MARKSDB_SMDRL_LOGIN_AND_PASSWORD,
   RDE_RECEIVER_PUBLIC_KEY,
   RDE_SIGNING_KEY_PAIR,
   RDE_SIGNING_PUBLIC_KEY,