fix(core): when debug-repl has duplicated providers

[micalevisk]

PR Checklist

Please check if your PR fulfills the following requirements:

• [x] The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• [x] 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?

• [x] Bugfix
• [x] 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 #9893 + one minor feature

(see the code below)

What is the new behavior?

Now the debug() function will

• display string tokens with double quotes, so we could easily distinguish between classes references, which also means that $("Foo") and $(Foo) aren't treated alike anymore. So we could have both providers (class Foo {} and { provide: "Foo", ... })
• display all those providers registered in the module properly

full code + demo

I'm not sure if treating string tokens in the same way as class references was intentional but I believe this decreases the flexiblity of the REPL

Does this PR introduce a breaking change?

• [ ] Yes
• [x] No(?)

[coveralls]

Pull Request Test Coverage Report for Build b8442661-5364-4fae-a4bf-b874ba5f565e

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 66 unchanged lines in 7 files lost coverage.
• Overall coverage increased (+0.09%) to 93.911%

---

Files with Coverage Reduction	New Missed Lines	%
packages/core/injector/lazy-module-loader.ts	3	76.0%
packages/microservices/server/server-kafka.ts	3	92.39%
packages/common/module-utils/configurable-module.builder.ts	5	91.84%
packages/microservices/server/server-rmq.ts	7	81.58%
packages/core/router/router-explorer.ts	13	79.88%
packages/core/injector/instance-wrapper.ts	17	85.92%
packages/microservices/client/client-rmq.ts	18	81.13%
<!--	Total:	66

Totals
Change from base Build bfe80734-d84f-4a6f-b9b5-a0e280824d1f:	0.09%
Covered Lines:	6030
Relevant Lines:	6421

---

💛 - Coveralls

[kamilmysliwiec]

lgtm