linkouts@v1.2.0

What's Changed

• changes to support trait (ie gwas and qtl_study) linkouts by @adf-ncgr in #617
• linkouts-v1.2.0 release by @adf-ncgr in #619

Full Changelog: https://github.com/legumeinfo/microservices/compare/linkouts@v1.1.0...linkouts@v1.2.0