ci: Test anchor-spl during downstream build (#34368)

* ci: Test anchor-spl during downstream build

* Also test anchor-client

* Update scripts/build-downstream-anchor-projects.sh

Co-authored-by: acheron <98934430+acheroncrypto@users.noreply.github.com>

* Specify features to use in build-sbf

---------

Co-authored-by: acheron <98934430+acheroncrypto@users.noreply.github.com>

scripts/build-downstream-anchor-projects.sh

@@ -59,6 +59,8 @@ anchor() {
   patch_crates_io_solana Cargo.toml "$solana_dir"
 
   $cargo test
+  (cd spl && $cargo_build_sbf --features dex metadata stake)
+  (cd client && $cargo test --all-features)
 
   anchor_dir=$PWD
   anchor_ver=$(readCargoVariable version "$anchor_dir"/lang/Cargo.toml)