Update duckdb index files

.gitattributes

@@ -191,3 +191,4 @@ dpr-first-20%-maxlen-500/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
 dpr-first-30%-maxlen-400/train/index.duckdb filter=lfs diff=lfs merge=lfs -text
 dpr-first-30%-maxlen-400/validation/index.duckdb filter=lfs diff=lfs merge=lfs -text
 dpr-first-30%-maxlen-400/test/index.duckdb filter=lfs diff=lfs merge=lfs -text
+dpr-first-30%-maxlen-300/train/index.duckdb filter=lfs diff=lfs merge=lfs -text

dpr-first-30%-maxlen-300/train/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:35732eccb44e004a3668bd51d2a3238979b3a13d4ee979295ba6f6c7695bc78c
+size 6828032