fix(common): fix @Inject and @Optional return types

[skrtheboss]

Use PropertyDecorator and ParameterDecorator as return type to ensure typings are correct

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: N/A

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[coveralls]

Pull Request Test Coverage Report for Build 83b3d2c7-f376-4160-a220-1097d54e8f18

• 2 of 2 (100.0%) changed or added relevant lines in 2 files are covered.
• 25 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.001%) to 92.655%

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Files with Coverage Reduction	New Missed Lines	%
packages/core/injector/module.ts	25	78.19%

Totals
Change from base Build 355edd54-ae26-4f3b-a472-2834ab2bca98:	-0.001%
Covered Lines:	6497
Relevant Lines:	7012

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💛 - Coveralls