fix etcd provider and router context usage

[KaymeKaydex]

• now if there is no etcd connection - etcd provider returns you error instead panic.
• etcd provider also accepts context as input for working with the logger.
• fixed the problem of re-creating a new context when starting discovery, which led to a lack of discovery logging.

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Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 69.88%. Comparing base (6019b45) to head (605c035).

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #92 +/- ## ======================================= Coverage 69.88% 69.88% ======================================= Files 11 11 Lines 704 704 ======================================= Hits 492 492 Misses 169 169 Partials 43 43 ```

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