Update duckdb index files

.gitattributes

@@ -65,3 +65,4 @@ default/encodec_24k/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/funcodec_en_libritts_16k_gr1nq32ds320/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/funcodec_en_libritts_16k_gr8nq32ds320/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/funcodec_en_libritts_16k_nq32ds320/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/funcodec_en_libritts_16k_nq32ds640/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/funcodec_en_libritts_16k_nq32ds640/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:292f4182774b8bbcf6709a36154077e328b6394250017a97d6b8f1388f75e46a
+size 233582592