fix broken SQL update

This fixes a bug in the generation of the SQL query, that was introduced
in 49dac92034.

There were two issues with the generation:
1. the check ids were sometimes not added to the arguments
2. the whereVals were not extracted as arguments

This lead to all arguments being treated as one, which caused all sorts
of errors in the frontend.
By extracting all whereVals and always building it with the check ids
first the update starts working correctly again.

Found-By: Parsa Yousefi <parsa.yousefi@ionos.com>

cmd/monfront/main.go

@@ -366,14 +366,14 @@ func checkAction(con *Context) {
 	}
 
 	sql := "update " + setTable + " set " + setClause + " where " + whereColumn + " = any($1::bigint[])"
-	if len(whereFields) > 0 {
 	whereVals = append([]any{pq.Array(&checks)}, whereVals...)
+	if len(whereFields) > 0 {
 		for i, column := range whereFields {
 			sql = sql + " and " + column + fmt.Sprintf(" = $%d", i+1)
 		}
 	}
 
-	_, err := DB.Exec(sql, whereVals)
+	_, err := DB.Exec(sql, whereVals...)
 	if err != nil {
 		con.w.WriteHeader(http.StatusInternalServerError)
 		fmt.Fprintf(con.w, "could not store changes")