Add "pin" to password-word-equivalents (Bug#35523)

* lisp/international/mule-conf.el (password-word-equivalents): Add "pin".
* test/lisp/comint-tests.el (comint-testsuite-password-strings): Add
test case.

lisp/international/mule-conf.el

@@ -1585,7 +1585,7 @@ for decoding and encoding files, process I/O, etc."
 (aset latin-extra-code-table ?\226 t)
 
 (defcustom password-word-equivalents
-  '("password" "passcode" "passphrase" "pass phrase"
+  '("password" "passcode" "passphrase" "pass phrase" "pin"
     ; These are sorted according to the GNU en_US locale.
     "암호"		; ko
     "パスワード"	; ja
@@ -1636,7 +1636,7 @@ password prompts, including prompts in languages other than
 English.  Different case choices should not be assumed to be
 included; callers should bind `case-fold-search' to t."
   :type '(repeat string)
-  :version "24.4"
+  :version "27.1"
   :group 'processes)
 
 ;; The old code-pages library is obsoleted by coding systems based on

test/lisp/comint-tests.el

@@ -37,6 +37,7 @@
     "Passphrase for key root@GNU.ORG: " ; plink
     "[sudo] password for user:" ; Ubuntu sudo
     "[sudo] user 的密码：" ; localized
+    "PIN for user:"        ; Bug#35523
     "Password (again):"
     "Enter password:"
     "Enter Auth Password:" ; OpenVPN (Bug#35724)