testing: remove obsolete daemon tests

remove all daemon version checks targeting daemons we no longer support.

Change-Id: If722024c3d66c73fa1b3cdd63134a09389ac6ea5

tests/functional/fetchClosure.sh

@@ -5,12 +5,6 @@ enableFeatures "fetch-closure"
 clearStore
 clearCacheCache
 
-# Old daemons don't properly zero out the self-references when
-# calculating the CA hashes, so this breaks `nix store
-# make-content-addressed` which expects the client and the daemon to
-# compute the same hash
-requireDaemonNewerThan "2.16.0pre20230524"
-
 # Initialize binary cache.
 nonCaPath=$(nix build --json --file ./dependencies.nix --no-link | jq -r .[].outputs.out)
 caPath=$(nix store make-content-addressed --json $nonCaPath | jq -r '.rewrites | map(.) | .[]')