patch 9.0.0828: various typos

Problem:    Various typos.
Solution:   Correct typos. (closes #11432)
diff --git a/src/dict.c b/src/dict.c
index 63b30e0..82c31de 100644
--- a/src/dict.c
+++ b/src/dict.c
@@ -1016,7 +1016,7 @@
 	    item = dict_find(d, key, -1);
 	    if (item != NULL)
 	    {
-		semsg(_(e_duplicate_key_in_dicitonary), key);
+		semsg(_(e_duplicate_key_in_dictionary), key);
 		clear_tv(&tvkey);
 		clear_tv(&tv);
 		goto failret;