Fix Js5MasterIndex creation if the LENGTHS format is used

The groups field is populated with the group capacity, not the group
size. (Thanks Ominious.)

Update the test to cover this case, by adjusting the test index so its
size and capacity are distinct.

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

cache/src/main/kotlin/org/openrs2/cache/Js5MasterIndex.kt

@@ -141,7 +141,7 @@ public data class Js5MasterIndex(
                             }
 
                             val version = index.version
-                            val groups = index.size
+                            val groups = index.capacity
                             val totalUncompressedLength = index.sumOf(Js5Index.Group<*>::uncompressedLength)
 
                             // TODO(gpe): should we throw an exception if there are trailing bytes here or in the block above?

cache/src/test/kotlin/org/openrs2/cache/Js5MasterIndexTest.kt

@@ -114,9 +114,9 @@ class Js5MasterIndexTest {
                 MasterIndexFormat.LENGTHS,
                 mutableListOf(
                     Js5MasterIndex.Entry(
-                        0x12345678, -1080883457, 3, 123, ByteBufUtil.decodeHexDump(
-                            "0bf30b80b7213154ada5c3797be15a8fbb6a96a80432e2093e10617bcb4e67de" +
-                                "9a858211cabe844c6fa3a1fbfe3164a3e4e1918983c69597dff3fc3c53096884"
+                        0x12345678, -817299640, 13, 123, ByteBufUtil.decodeHexDump(
+                            "7c2eb43256e9350b637d0ca819813fa3397bc6035a72c6c7e41b714b74301c7e" +
+                                "bba0e6b5408cb2514656181b75f2040397e4eb6944456ce60ca337a32a1c4f05"
                         )
                     )
                 )