Fix Participant form test to correctly test html version

[eileenmcnaughton]

We were checking for text that is present on the text version - but not the html. This blanks out the text version in the test (soon to be global) so that we are testing the html version

In this case the html version is right - ie we only show paid amount & balance if relevant - ie if part payment has been made. If it is all paid or all unpaid we don't

[civibot]

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