refactor: move connecting state logic into proper methods

[arthurschreiber]

This moves the logic that lived in the connection state machine into proper methods.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 61.72840% with 62 lines in your changes missing coverage. Please review.

Project coverage is 85.47%. Comparing base (aa0f183) to head (7ba5ddb). Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/connection.ts	61.72%	61 Missing and 1 partial :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #1661 +/- ## ======================================= Coverage 85.46% 85.47% ======================================= Files 90 90 Lines 4857 4859 +2 Branches 924 924 ======================================= + Hits 4151 4153 +2 Misses 702 702 Partials 4 4 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.