Update apache-avro to v0.21.0 (#1881)

## Which issue does this PR close?
None

## What changes are included in this PR?
Upgrades `apache-avro` from `0.20.0` to `0.21.0` in order to get rid of
the deprecated `xz2` crate.

## Are these changes tested?
Build & tests succeeds

Author: N-Boutaib

Cargo.lock

@@ -40,7 +40,7 @@ rust-version = "1.87"
 
 [workspace.dependencies]
 anyhow = "1.0.72"
-apache-avro = { version = "0.20", features = ["zstandard"] }
+apache-avro = { version = "0.21", features = ["zstandard"] }
 array-init = "2"
 arrow-arith = "56.2"
 arrow-array = "56.2"