conditional_fields 8.x-1.0-alpha5

Here's another alpha. If you'd like a beta, then please help with #2830988: [meta] 4.0.0 release roadmap.

Changes since 8.x-1.0-alpha4:

• #2874729 by Pavan B S, piggito: Replace all usages of deprecated EntityManagerInterface (#)
• #2893597 by geovanni.conti: Check if the list of options is empty before using it. (#)
• #2950955 by User Advocate: Check for array index before using it. (#)
• #2892832 by cslevy, Vitalyos, axel.rutz: Blank screen when saving the node that has a condition with "required" field (#)
• #2983376 by axel.rutz: Action "Empty" has no effect (#)
• #2983381 by axel.rutz: Make invisible imply unrequired and empty (#)
• #2983462 by axel.rutz: Fix required-handling (#)
• #3024475 by thalles: Use dependency injection in Form/ConditionalFieldForm.php. (#)
• #3024485 by thalles: Use dependency injection in Form/ConditionalFieldEditForm.php. (#)
• #3024493 by thalles: Added missing blank line at end of file. (#)
• #2998570 by chipway: Applied new {project}:{module} format for dependencies in info.yml. (#)