Add support for npm ci on different CPU architecture or OS

[kethinov]

At present fallback-dependencies will always run npm ci without any arguments, like the ability to specify the desired --cpu or --os but to handle situations like this we should make that possible.

To do that, we should probably expose new environment variables that, if present, will make fallback-dependencies run npm ci with those flags enabled.

Examples:

• FALLBACK_DEPENDENCIES_TARGET_CPU being set to arm64
• FALLBACK_DEPENDENCIES_TARGET_OS being set to darwin
• etc