fix(graphql): Support @Field of list type in IntersectionType

[exarus]

PR Checklist

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• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Other... Please describe:

What is the current behavior?

Issue Number: #1420

What is the new behavior?

IntersectionType
Fix @field of List type in IntersectionType.
Previously array wrapper was ignored and GraphQL List wrapper was not applied:

// [String] was interpreted as String
@Field(() => [String])

In suggested changes IntersectionType executes type function to support GraphQL List types.
Other helpers (PickType, OmitType) are using same approach.

Does this PR introduce a breaking change?

• Yes
• No

Other information

Previous PR (#1420) executed type functions eagerly, so could not be merged.
Furthermore it was abandoned more than a year ago, closed for commenting and modification.

[kamilmysliwiec]

LGTM