Convert to domain extension to enable authenticated requests

...keycloak/files/providers/keycloak-mailpass-rest/README.md

...k/files/providers/keycloak-mailpass-rest/build.gradle.kts

...ers/keycloak-mailpass-rest/docker/invoke-authenticated.sh

...rg/archlinux/keycloak/mailpass/rest/MailPassResource.java

...inux/keycloak/mailpass/rest/MailPassResourceProvider.java

...ycloak/mailpass/rest/MailPassResourceProviderFactory.java

...rchlinux/keycloak/mailpass/rest/MailPassRestResource.java

...rc/main/resources/META-INF/jboss-deployment-structure.xml