Update passwd-expect -ssh to allow for ECDSA (#6574)

fingerprint_string could have different wording on a modern installation if the server key is not RSA

plugins/password/helpers/passwd-expect

@@ -43,7 +43,7 @@ set host               "localhost"
 set login              "ssh"
 set program            "passwd"
 set prompt_string      "(%|\\\$|>)"
-set fingerprint_string "The authenticity of host.* can't be established.*\nRSA key fingerprint is.*\nAre you sure you want to continue connecting.*"
+set fingerprint_string "The authenticity of host.* can't be established.*\n(RSA|ECDSA) key fingerprint is.*\nAre you sure you want to continue connecting.*"
 set password_string    "(P|p)assword.*"
 set oldpassword_string "((O|o)ld|login|\\\(current\\\) UNIX) (P|p)assword.*"
 set newpassword_string "(N|n)ew.* (P|p)assword.*"