Fix inconsistency with arrow-integrations-jackson-module and arrow-integrations-retrofit-adapter

[rachelcarmena]

Directories and package end with 's', however it's missing in artifact id:

• arrow-integrations-retrofit-adapter/gradle.properties

  # Maven publishing configuration
  POM_NAME=Arrow-Integrations-Retrofit-Adapter
  POM_ARTIFACT_ID=arrow-integration-retrofit-adapter
  POM_PACKAGING=jar

• arrow-integrations-jackson-module/gradle.properties

  # Maven publishing configuration
  POM_NAME=Arrow-Integrations-Jackson-Module
  POM_ARTIFACT_ID=arrow-integration-jackson-module
  POM_PACKAGING=jar

So the artifacts are published without 's':

• https://mvnrepository.com/artifact/io.arrow-kt/arrow-integration-retrofit-adapter
• Arrow-Integrations-Jackson-Module isn't in Central Maven Repository yet, just OSS: https://oss.jfrog.org/artifactory/oss-snapshot-local/io/arrow-kt/arrow-integration-jackson-module/