bug: fixed brightness filter tagline warning

Author: harshsankhla18

filter.c

@@ -7,7 +7,7 @@
 int main(int argc, char *argv[])
 {
     // Define allowable filters
-    char *filters = "bgrsivtdB:G";
+    char *filters = "bgrsivtdGB:";
 
 
     char filterArr[argc-3];
@@ -181,4 +181,4 @@ int main(int argc, char *argv[])
     fclose(inptr);
     fclose(outptr);
     return 0;
-}
+}