Fix SkipOutputStream

Calling super.write(byte[], int, int) in FilterOutputStream didn't work,
as it called super.write(byte). This is inefficient and also caused us
to fiddle with skipBytes twice, causing us to skip the incorrect number
of bytes.

common/src/main/java/dev/openrs2/common/io/SkipOutputStream.kt

@@ -1,12 +1,11 @@
 package dev.openrs2.common.io
 
-import java.io.FilterOutputStream
 import java.io.OutputStream
 
-class SkipOutputStream(out: OutputStream, private var skipBytes: Long) : FilterOutputStream(out) {
+class SkipOutputStream(private val out: OutputStream, private var skipBytes: Long) : OutputStream() {
     override fun write(b: Int) {
         if (skipBytes == 0L) {
-            super.write(b)
+            out.write(b)
         } else {
             skipBytes--
         }
@@ -14,10 +13,18 @@ class SkipOutputStream(out: OutputStream, private var skipBytes: Long) : FilterO
 
     override fun write(b: ByteArray, off: Int, len: Int) {
         if (len >= skipBytes) {
-            super.write(b, off + skipBytes.toInt(), len - skipBytes.toInt())
+            out.write(b, off + skipBytes.toInt(), len - skipBytes.toInt())
             skipBytes = 0
         } else {
             skipBytes -= len
         }
     }
+
+    override fun flush() {
+        out.flush()
+    }
+
+    override fun close() {
+        out.close()
+    }
 }