[cdk8s-plus] Simplify cdk8s-plus API by removing the spec nesting level

[iliapolo]

Description of the feature or enhancement:

Instead of:

new kplus.Pod(this, 'Pod' {
  spec: {
    containers: ...
  }
})

Lets have this:

new kplus.Pod(this, 'Pod' {
  containers: ...
})

Use Case:

Better API ergonomics

Proposed Solution:

Other:

• What about possibly collisions with the metadata property?

• 👋 I may be able to implement this feature request
• ⚠️ This feature might incur a breaking change

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This is a 🚀 Feature Request

[iliapolo]

Resolved by #347