Participant Calculate/Fees: fix ts usage, simplify wording

[mlutfy]

Overview

Fixes an incorrect use of ts, which assumes how strings can be concatenated. It also makes it difficult to use Word Replacements.

After:

Comments

I wanted to override the wording to simplify display "Total". It was not possible because of how the strings are concatenated.

Using wording such as "Fee(s)" really looks clunky, but will avoid changing the priceset title for now.

[civibot]

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[eileenmcnaughton]

Seems fine to me - simpler & more generic is better IMHO