Fix bad i18n string (#46454)

Fixes #46440

couple things come together here.

Bad escaping:
The `{` characters are used for format strings and placeholders like

```clojure
impl=> (translate "fr" "After {0}" ["Bob"])
"Après Bob"
```

And if you want _literal_ {'s in your translation string, you must
escape them like "'{" or "'}" using an apostrophe. But this isn't the
end of our worries.

in `resources/zh-CN.edn`, we actually have _two_ translations for the
original string:

```clojure
"User lookup filter. The placeholder '{login'} will be replaced by the user supplied login."
"用户找过滤器，占位符 '{login'} 将替换为用户提供的登录名。"

,,,

"User lookup filter. The placeholder '{login}' will be replaced by the user supplied login."
"用户查找筛选器。占位符“{login}”将替换为用户提供的登录名。"
```

And this later has unescaped curlies.

The fix for that is at
https://poeditor.com/projects/po_edit?per_page=20&id=200535&id_language=31&filter=&order=&search=User+lookup+filter
but will need to wait for the new source translation string in this
instance with the corrected escaping.

```clojure
;; simulate what happens at runtime
impl=> (translated-format-string "zh_CN"
                                 "User lookup filter. The placeholder '{login}' will be replaced by the user supplied login."
                                 {})
"用户查找筛选器。占位符“{login}”将替换为用户提供的登录名。"
impl=> (MessageFormat. *1 (locale "zh_CN"))
Execution error (NumberFormatException) at java.lang.NumberFormatException/forInputString (NumberFormatException.java:67).
For input string: "login"
;; the problematic zh-CN string
impl=> (MessageFormat. "用户查找筛选器。占位符“{login}”将替换为用户提供的登录名。")
Execution error (NumberFormatException) at java.lang.NumberFormatException/forInputString (NumberFormatException.java:67).
For input string: "login"
;; minimal reproduction
impl=> (MessageFormat. "“{login}”")
Execution error (NumberFormatException) at java.lang.NumberFormatException/forInputString (NumberFormatException.java:67).
For input string: "login"
```

src/metabase/integrations/ldap.clj

@@ -56,7 +56,7 @@
   :audit :getter)
 
 (defsetting ldap-user-filter
-  (deferred-tru "User lookup filter. The placeholder '{login}' will be replaced by the user supplied login.")
+  (deferred-tru "User lookup filter. The placeholder '{login'} will be replaced by the user supplied login.")
   :default "(&(objectClass=inetOrgPerson)(|(uid={login})(mail={login})))"
   :audit   :getter)