CHANGE: using lower default compression level for Brotli compression

Author: Oldes

src/core/u-compress.c

@@ -379,7 +379,7 @@ void BrotliDefaultFreeFunc(void* opaque, void* address) {
 	REBYTE *inp;
 
 	if (level < 0)
-		level = 9;
+		level = 6;
 	else if (level > 11)
 		level = 11;