bug/1588: fix post-retrieve processing of transactional email journeys

[JoernBerkefeld]

PR details

What changes did you make? (Give an overview)

• closes [BUG] downloading transactional journeys shows warning about triggeredSend not found #1588

Further details (optional)

...

Checklist

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• test scripts updated
• Wiki updated (if applicable)

[github-actions]

Coverage Report

Commit:199be04
Base: develop@fab9f62

Type	Base	This PR
Total Statements Coverage	71.34%	71.31%  (-0.03%)
Total Branches Coverage	69.76%	69.7%  (-0.06%)
Total Functions Coverage	82.87%	82.87%  (+0%)
Total Lines Coverage	71.34%	71.31%  (-0.03%)

Details (changed files):

File	Statements	Branches	Functions	Lines
lib/metadataTypes/Journey.js	61.99%	62.42%	88.23%	61.99%