Support per-platform container options #6171

Act version

v0.2.89

Feature description

Add per-platform container options for workflows that mix runner types:

--container-options '--cpus 4'
--platform-options big-cpu-runner='--cpus 16'
--platform-options gpu-runner+='--gpus all'

• Keep --container-options as the global default options for platform containers.
• Override global defaults with --platform-options platform-name='options'
• Append global defaults with --platform-options platform-name+='options'