Fix MacVim's Korean menu translations causing startup error

Apple's Korean translations contain individual "." instead of using
ellipsis, and the extraction script wasn't escapting them when using
them in `menutrans` commands. Add the escape and re-generate the Korean
menu translations.

Fix #1278

runtime/lang/macvim_menu/menu_ko_kr.utf-8.apple.vim

@@ -7,7 +7,7 @@ menutrans Open… 열기…
 menutrans Open\ Recent 최근\ 사용\ 열기
 menutrans Close\ Window<Tab>:qa 윈도우\ 닫기
 menutrans Close<Tab>:q 닫기
-menutrans Save\ As…<Tab>:sav 별도\ 저장...
+menutrans Save\ As…<Tab>:sav 별도\ 저장\.\.\.
 menutrans Save\ All 모두\ 저장
 menutrans Find 찾기
 menutrans Find… 찾기…

src/MacVim/scripts/extract-specific-localised-strings.swift

@@ -363,6 +363,7 @@ for localisation in localisations {
             else {
                 let escapedTranslation = translation.replacingOccurrences(of: " ", with: "\\ ", options: .literal, range: nil)
                                                     .replacingOccurrences(of: " ", with: "\\ ", options: .literal, range: nil)
+                                                    .replacingOccurrences(of: ".", with: "\\.", options: .literal, range: nil)
 
                 return """
                 menutrans \(neededLocalisation.targetKey) \(escapedTranslation)