APB-7274 [CS] add phone number to agency details

Scala can be updated from 2.12.15 to 2.13.8 in build.sbt - See confluence https://confluence.tools.tax.service.gov.uk/x/L4HJHw
System property lookup can be removed in conf/application-json-logger.xml - Bootstrap's LoggerModule allows configuration of loggers without this - See confluence https://confluence.tools.tax.service.gov.uk/x/9oH1FQ
Add uk.gov.hmrc.bootstrap-test-play-28 in project/AppDependencies.scala to provide recommended test dependencies. Use a variable to keep version in sync with bootstrap-play
Looks like @Singleton is missing on app/uk/gov/hmrc/agentclientauthorisation/repository/AgentSuspensionContactDetailsCapturedRepository.scala. Only one instance is preferable as indexes would be reinitalised - see https://github.com/hmrc/hmrc-mongo#playmongorepository

hmrc / agent-client-authorisation