Make BATCH_SIZE const

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

archive/src/main/kotlin/org/openrs2/archive/cache/CacheExporter.kt

@@ -60,6 +60,6 @@ public class CacheExporter @Inject constructor(
     }
 
     private companion object {
-        private val BATCH_SIZE = 1024
+        private const val BATCH_SIZE = 1024
     }
 }

archive/src/main/kotlin/org/openrs2/archive/cache/CacheImporter.kt

@@ -370,6 +370,6 @@ public class CacheImporter @Inject constructor(
     }
 
     private companion object {
-        private val BATCH_SIZE = 1024
+        private const val BATCH_SIZE = 1024
     }
 }