patch 8.1.0797: error E898 is used twice

Problem:    Error E898 is used twice.
Solution:   Rename the Blob error to E899. (closes #3853)
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 11884ab..e0f5d6e 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -29,7 +29,7 @@
 #endif
 
 static char *e_listarg = N_("E686: Argument of %s must be a List");
-static char *e_listblobarg = N_("E898: Argument of %s must be a List or Blob");
+static char *e_listblobarg = N_("E899: Argument of %s must be a List or Blob");
 static char *e_stringreq = N_("E928: String required");
 
 #ifdef FEAT_FLOAT