Logging WebDAV credentials prompts

(cherry picked from commit fcfeb83309fc1c523e5be0cdf0661c54031a2204)

Source commit: e926860c46734529fe11b1d123828e3a3b1b8f81

source/core/WebDAVFileSystem.cpp

@@ -1827,6 +1827,7 @@ int TWebDAVFileSystem::NeonRequestAuth(
     }
     else
     {
+      Terminal->LogEvent(L"Username prompt");
       if (!Terminal->PromptUser(SessionData, pkUserName, LoadStr(USERNAME_TITLE), L"",
             LoadStr(USERNAME_PROMPT2), true, NE_ABUFSIZ, FileSystem->FUserName))
       {
@@ -1873,6 +1874,7 @@ int TWebDAVFileSystem::NeonRequestAuth(
         // Asking for password (or using configured password) the first time,
         // and asking for password.
         // Note that we never get false here actually
+        Terminal->LogEvent(L"Password prompt");
         Result =
           Terminal->PromptUser(
             SessionData, pkPassword, LoadStr(PASSWORD_TITLE), L"",