patch 8.2.1154: Vim9: crash when using imported function

Problem:    Vim9: crash when using imported function.
Solution:   Check for a function type.  Set the script context when calling a
            function. (closes #6412)

src/structs.h

@@ -1905,6 +1905,9 @@ typedef struct {
 	AutoPatCmd *aucmd;  // autocommand info
 	except_T   *except; // exception info
     } es_info;
+#if defined(FEAT_EVAL)
+    scid_T	es_save_sid;	    // saved sc_sid when calling function
+#endif
 } estack_T;
 
 // Information returned by get_tty_info().