Use result instead of unwrap in apub tests (#4168)

api_tests/pict-rs

api_tests/yarn-error.log

crates/apub/src/activity_lists.rs

crates/apub/src/api/user_settings_backup.rs

crates/apub/src/collections/community_moderators.rs

crates/apub/src/objects/comment.rs

crates/apub/src/objects/community.rs

crates/apub/src/objects/instance.rs

crates/apub/src/objects/mod.rs

crates/apub/src/objects/person.rs

crates/apub/src/objects/post.rs

crates/apub/src/objects/private_message.rs

crates/apub/src/protocol/activities/block/mod.rs

crates/apub/src/protocol/activities/community/mod.rs

crates/apub/src/protocol/activities/create_or_update/mod.rs

crates/apub/src/protocol/activities/deletion/mod.rs

crates/apub/src/protocol/activities/following/mod.rs

crates/apub/src/protocol/activities/mod.rs

crates/apub/src/protocol/activities/voting/mod.rs

crates/apub/src/protocol/collections/mod.rs