Update duckdb index files

.gitattributes

@@ -137,3 +137,4 @@ default/opendata.stackexchange.com/index.duckdb filter=lfs diff=lfs merge=lfs -t
 default/opensource.stackexchange.com/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/or.stackexchange.com/index.duckdb filter=lfs diff=lfs merge=lfs -text
 default/quantumcomputing.stackexchange.com/index.duckdb filter=lfs diff=lfs merge=lfs -text
+default/retrocomputing.stackexchange.com/index.duckdb filter=lfs diff=lfs merge=lfs -text

default/retrocomputing.stackexchange.com/index.duckdb

@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:c8f8f3342444830343b58962aa0d3f8d581a06334a99de31db0f8d552599f599
+size 5779456