Fix registration of dev provider in Service.authMiddleware.Providers

[cyb3r4nt]

There was one minor problem related to the dev and Apple providers registration.

Now it is possible to have a configuration,
where only one single dev provider is enabled.

Providers were not registered into Service.authMiddleware.Providers slice in the Service.AddDevProvider() and Service.AddAppleProvider() methods before.

This worked before, because other providers were registered at the same time, and authMiddleware.Providers slice was reassigned by other methods.

[paskal]

I reviewed the changes and I think they are not breaking anything.

The only thing I still do not understand is the original issue, could you please describe it in more detail, and maybe provide a code snippet which reproduces it? Ideally a test which reproduces the problem in master.

[coveralls]

Pull Request Test Coverage Report for Build 9349982315

Details

• 22 of 24 (91.67%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.02%) to 82.73%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
v2/auth.go	22	24	91.67%

Totals
Change from base Build 8627959567:	-0.02%
Covered Lines:	2558
Relevant Lines:	3092

---

💛 - Coveralls

[cyb3r4nt]

The only thing I still do not understand is the original issue, could you please describe it in more detail, and maybe provide a code snippet which reproduces it? Ideally a test which reproduces the problem in master.

I was trying to use this auth lib in my dev environment, and only a single dev provider was configured there.
It is possible to reproduce it with TestIntegrationProtected and commenting out all other providers in prepService() preparation method
This check was failing for me during the request to some protected web endpoint.
Same thing may be reproduced if remark42 is started only with option --auth.dev and without specifying any other providers.

The new and modified version of TestIntegrationProtected from this PR should cover this issue.

[coveralls]

Pull Request Test Coverage Report for Build 9387863023

Details

• 24 of 24 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.6%) to 83.344%

---

Totals
Change from base Build 8627959567:	0.6%
Covered Lines:	2577
Relevant Lines:	3092

---

💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 9387863020

Details

• 24 of 24 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.6%) to 83.344%

---

Totals
Change from base Build 8627959567:	0.6%
Covered Lines:	2577
Relevant Lines:	3092

---

💛 - Coveralls

[paskal]

@umputun, this one is good to merge.

@cyb3r4nt, please prepare an MR to v2, which would prohibit underscore in the provider name; that would be good if we know it breaks something.

[umputun]

LGTM, thx