Ability to set node properties for fleet nodes

[amezentzev]

Is your feature request related to a problem? Please describe.
Generic jenkins UI provides nice ability to set build node's 'node properties', specifically environment variables and job execution restrictions by regex pattern, would be great to have this supported by ec2 fleet plugin.

Describe the solution you'd like
Expected solution is to add ability to set node properties in ec2 fleet configuration, either using ui or jcasc.

Describe alternatives you've considered
If there is another way to configure it, please share such solution or update documentation for plugin.

[aluczakSumo]

➕ (my similar issue already got closed due to staleness #340 )