refactor: require ledger transport to be explicitly passed in

[faustbrian]

The way the ledger transport is built isn't optimal to say the least because it executes things simply by requiring it which results in unwanted side-effects before you even use the library.

This PR changes the public API of the ledger services to require the transport to be explicitly passed in by consumers which will make it possible to require the transport only when it is needed and avoid any global side-effects.

[codecov]

Codecov Report

Merging #441 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #441   +/-   ##
=======================================
  Coverage   72.00%   72.00%           
=======================================
  Files          50       50           
  Lines         950      950           
  Branches       67       67           
=======================================
  Hits          684      684           
  Misses        241      241           
  Partials       25       25           

Flag	Coverage Δ
#unit	72.00% <ø> (ø)

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