patch 8.2.2842: Vim9: skip argument to searchpair() is not compiled

Problem:    Vim9: skip argument to searchpair() is not compiled.
Solution:   Add VAR_INSTR.
diff --git a/src/vim.h b/src/vim.h
index ead0c56..368cf32 100644
--- a/src/vim.h
+++ b/src/vim.h
@@ -2030,6 +2030,7 @@
 #define VAR_TYPE_JOB	    8
 #define VAR_TYPE_CHANNEL    9
 #define VAR_TYPE_BLOB	    10
+#define VAR_TYPE_INSTR	    11
 
 #define DICT_MAXNEST 100	// maximum nesting of lists and dicts