v2.4.0

What's Changed

• add: MySQL test by @kazumatsudo in #114
• set vertex.id and edge.id primary key by @kazumatsudo in #116
• add: set (edge.id_in_v, edge.id_out_v) unique index by @kazumatsudo in #117
• chore(deps): update dependency com.mysql:mysql-connector-j to v8.3.0 by @renovate in #115
• add: set edge.id_in_v and edge.id_out_v each foreign key reference vertex one by @kazumatsudo in #118
• add: test for RelationIdentifier by @kazumatsudo in #119

Full Changelog: v2.3.0...v2.4.0