patch 8.2.0334: abort called when using test_void()

Problem:    Abort called when using test_void(). (Dominique Pelle)
Solution:   Only give an error, don't abort.
diff --git a/src/message.c b/src/message.c
index c2855fb..cb1a773 100644
--- a/src/message.c
+++ b/src/message.c
@@ -838,6 +838,16 @@
     siemsg(_(e_intern2), where);
 }
 
+/*
+ * Like internal_error() but do not call abort(), to avoid tests using
+ * test_unknown() and test_void() causing Vim to exit.
+ */
+    void
+internal_error_no_abort(char *where)
+{
+     semsg(_(e_intern2), where);
+}
+
 // emsg3() and emsgn() are in misc2.c to avoid warnings for the prototypes.
 
     void