feat(postgres): idle_in_transaction_session_timeout connection option

[aheuermann]

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Description of change

Exposing the postgres idle_in_transaction_session_timeout connection parameter. It was added in node-postgres v7.17.0 and only exposed in postgres v10 and greater.

Not sure if it is possible or the best way to write a test for this. So let me know if you have ideas.

Thanks!

[codecov]

Codecov Report

Merging #11775 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #11775   +/-   ##
=======================================
  Coverage   96.26%   96.26%           
=======================================
  Files          94       94           
  Lines        9191     9191           
=======================================
  Hits         8848     8848           
  Misses        343      343

Impacted Files	Coverage Δ
lib/model.js	96.54% <ø> (ø)	⬆️
lib/sequelize.js	95.93% <ø> (ø)	⬆️

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