Fix @kogito-apps/process-form: doesn't display custom forms.

[pefernan]

Although the form-generation-tool generates the process forms, the process-form component still uses the default autogenerated form... we should make it use the custom if provided by the app.

Steps to reproduce:

1. Generate patternfly forms using form-generation-tool for any BPM Quarkus project in kogito-examples (for example process-usertasks-quarkus-with-console)
2. In the project pom.xml add a dependency to the runtime-tools-quarkus-extension
3. Start the Kogito project in dev mode (mvn clean quarkus:dev)
4. Open the Dev ui (http://locahost:8080/q/dev) and click on the Process Instances link inside the Runtime Tools Quarkus Extension and start a new process instance, de default form will be displayed instead of the one generated by the form-generation-tool

[jomarko]

Will be addressed via apache/incubator-kie-kogito-apps#1927