[Cashtab] Patch collapse proptype error

Summary: Related to T2479. Changed optionalDefaultActiveKey propType from PropTypes.bool to PropTypes.arrayOf(PropTypes.string).

Test Plan:
cd web/cashtab && npm start
Observe that the optionalDefaultActiveKey console error does not appear in the log.

grep -r 'optionalDefaultActiveKey: Proptypes.bool' src/ should return null

Reviewers: bytesofman, #bitcoin_abc

Reviewed By: bytesofman, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D11614