jboss-eap-installation-manager.sh fails to install feature-pack org.keycloak:keycloak-saml-adapter-galleon-pack on JBoss EAP 8

Issue

• When installing the gallean feature pack for Keycloak SAML adapter, the stack trace error below can be observed:

$ ./bin/jboss-eap-installation-manager.sh feature-pack add --layers=keycloak-client-saml,keycloak-client-saml-ejb --fpl=org.keycloak:keycloak-saml-adapter-galleon-pack -vv
Installing feature pack `org.keycloak:keycloak-saml-adapter-galleon-pack` in server `/jboss-eap-8.0/.`
Continue adding the feature pack? [y/N]:y
Applying changes

Feature-packs resolved.                                                           


Failed to parse provisioning configuration: /layers/standalone/keycloak-client-saml/layer-spec.xml

org.jboss.galleon.ProvisioningException: Failed to parse /layers/standalone/keycloak-client-saml/layer-spec.xml
...
Caused by: org.jboss.galleon.ProvisioningException: Failed to parse config layer spec
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Caused by: javax.xml.stream.XMLStreamException: ParseError at [row,col]:[2,82]
Message: Unexpected element '{urn:jboss:galleon:layer-spec:2.0}layer-spec'
...