fix: fastify-adapter register func sign #10604

[ufec]

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: #10604

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[ufec]

after run build, in example 10-fastify, is ok

[coveralls]

Pull Request Test Coverage Report for Build c99b302d-acdd-4ab3-b096-f9ad3e503c75

• 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 93.404%

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Totals
Change from base Build a213a525-4c5b-48ee-9803-b76e72178509:	0.0%
Covered Lines:	6202
Relevant Lines:	6640

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💛 - Coveralls

[kamilmysliwiec]

LGTM

[ufec]

It's a great honor to be a contributor, I'm using nestjs recently, I hope it will get better and better