Decouple NewKeyringFromDir() from sdk.GetConfig()

[alessio]

NewKeyringFromDir() takes only a keyring service name, which
becomes a component of the directory used as keyring's storage.

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[alessio]

No changelog entry is required as the kerying hasn't been released yet

[fedekunze]

utACK

[alexanderbez]

Reviewing this PR has me thinking that the constructors as they are now may not make the most sense, namely, NewKeyring*, which internally makes some use of viper.

I would propose we instead have a single constructor:

NewKeyring(svcName, backend, rootDir string, input io.Reader, opts ...keys.KeybaseOption)

Force the upstream caller to provide svcName, backend, rootDir. The caller may then use viper and sdk.GetConfig() as they wish. Thoughts?

[alessio]

I like it @alexanderbez! Do you mind if I do this change in an ensuing PR?

[jackzampolin]

I think thats a great idea @alexanderbez and one that we should follow through on. This PR seems a good venue to deal with that.

[alexanderbez]

I like it @alexanderbez! Do you mind if I do this change in an ensuing PR?

Mhhh, may I ask why? It would undo the work in this PR essentially. In addition, the changes would be pretty minimal and trivial.

[alexanderbez]

ACK 🎉

[codecov]

Codecov Report

Merging #5547 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #5547      +/-   ##
==========================================
+ Coverage   54.15%   54.16%   +0.01%     
==========================================
  Files         313      313              
  Lines       18960    18960              
==========================================
+ Hits        10268    10270       +2     
+ Misses       7894     7892       -2     
  Partials      798      798

Impacted Files	Coverage Δ
x/mock/app.go	64.18% <0%> (+1.35%)	⬆️