Update duckdb index files

.gitattributes

@@ -68,3 +68,4 @@ default/encodec_24k_6bps/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:e0c4dbd1a070d15b98eac9a2c671c0d01c5e3e3942aac66cf80134229142e6fb
+size 18624512