patch 9.0.1594: some internal error messages are translated

Problem:    Some internal error messages are translated.
Solution:   Consistently do not translate internal error messages.
            (closes #12459)
diff --git a/src/version.c b/src/version.c
index 3f0eb0d..e4dc511 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1594,
+/**/
     1593,
 /**/
     1592,