fix: trained zstd test by restoring artifacts/lib.rs

Author: arpankapoor

tests/artifacts/lib.rs

@@ -87,14 +87,6 @@
     not(feature = "gzip"),
     doc = "`gzip` (*inactive*) | `GzipEncoder`, `GzipDecoder`"
 )]
-#![cfg_attr(
-    feature = "lz4",
-    doc = "`lz4` | [`Lz4Encoder`](?search=Lz4Encoder), [`Lz4Decoder`](?search=Lz4Decoder)"
-)]
-#![cfg_attr(
-    not(feature = "lz4"),
-    doc = "`lz4` (*inactive*) | `Lz4Encoder`, `Lz4Decoder`"
-)]
 #![cfg_attr(
     feature = "lzma",
     doc = "`lzma` | [`LzmaEncoder`](?search=LzmaEncoder), [`LzmaDecoder`](?search=LzmaDecoder)"