Add payjoin-mailroom to test_local.sh

It was omitted unintentionally before

Author: spacebear21

AGENTS.md

@@ -35,7 +35,7 @@ codespell
 ./contrib/lint.sh
 RUSTDOCFLAGS="-D warnings" cargo doc --no-deps --all-features \
   --document-private-items
-./contrib/test_local.sh            # does NOT include payjoin-mailroom
+./contrib/test_local.sh
 treefmt --ci                       # prettier, taplo, nixfmt, shellcheck, shfmt
 codespell
 ```

contrib/test_local.sh

@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 set -e
 
-CRATES="ohttp-relay payjoin payjoin-cli payjoin-directory payjoin-ffi"
+CRATES="ohttp-relay payjoin payjoin-cli payjoin-directory payjoin-ffi payjoin-mailroom"
 
 cargo --version
 rustc --version