Fix reading timestamps with sign bit set

lo should've been masked rather than hi. I've switched the code to mask
both the low and high DWORDs for simplicity.

Signed-off-by: Graham <gpe@openrs2.org>

archive/src/main/kotlin/org/openrs2/archive/cache/finder/CacheFinderExtractor.kt

@@ -22,7 +22,7 @@ public class CacheFinderExtractor(
     private val input = LittleEndianDataInputStream(pushbackInput)
 
     private fun readTimestamp(): FileTime {
-        val lo = input.readInt().toLong()
+        val lo = input.readInt().toLong() and 0xFFFFFFFF
         val hi = input.readInt().toLong() and 0xFFFFFFFF
 
         val seconds = (((hi shl 32) or lo) / 10_000_000) - FILETIME_TO_UNIX_EPOCH
@@ -102,7 +102,7 @@ public class CacheFinderExtractor(
             val atime = readTimestamp()
             val mtime = readTimestamp()
 
-            val sizeHi = input.readInt().toLong()
+            val sizeHi = input.readInt().toLong() and 0xFFFFFFFF
             val sizeLo = input.readInt().toLong() and 0xFFFFFFFF
             val size = (sizeHi shl 32) or sizeLo