AGR 5.3.0 Release

What's Changed

• Removed hardcoding of release version as it needs to be passed via ENV by @oblodgett in #625
• KANBAN-173 First pass on Xenbase changes by @christabone in #624
• Modifed entries for Xenbase FASTA by @christabone in #627
• Avoid issues with duplicate transcript names across MODs by @markquintontulloch in #629
• Loader test fixes (maybe) by @markquintontulloch in #630
• SCRUM-1809 Replace CREATE queries with MERGE by @markquintontulloch in #623
• Update default_env_vars.yml by @christabone in #628
• Fixed ETL helper to allow XB genes to load properly in orthology. by @christabone in #631
• KANBAN-173 Orthology ETL fix by @christabone in #632
• Update specific_tests.py by @christabone in #634
• fix(disease_via_ortho): using undirected relationship to read ortho data for disease via ortho by @valearna in #635
• Removed chromosome relationship from GL and lines cleanup by @oblodgett in #636
• Scrum 1207 - XB gene descriptions by @valearna in #637
• Fix species name and taxon id in descriptions download files header (tsv and txt) by @valearna in #638

Full Changelog: 5.2.0...5.3.0