feat(plataform-express): replace any return type on #listen with Server

[micalevisk]

PR Checklist

Please check if your PR fulfills the following requirements:

• 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: closes #10480

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

[coveralls]

Pull Request Test Coverage Report for Build ca801b5e-f0f1-4567-b1a4-c661deb3a4b1

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 93.788%

---

Totals
Change from base Build a1f147f5-1d97-43a6-8bf9-8ee0113704c9:	0.0%
Covered Lines:	6115
Relevant Lines:	6520

---

💛 - Coveralls

[kamilmysliwiec]

lgtm