create cypress tests for impress iconviews

[printfdebugging]

This is an Easy Hack. Potential mentors: @Darshan-upadhyay1110 @printfdebugging

Detailed description and rationale

https://github.com/CollaboraOnline/online/pull/12654 added a new expander button to the iconviews, please see the commits and screenshots for more details.

Code pointers

• https://github.com/CollaboraOnline/online/pull/12654/commits/d21649010335e76f94c029f04ea9eac4a278e8c7 adds cypress tests for writer stylesview. we need tests for the 'transitions iconview' and the 'master slide templates' iconviews which are located on the transition and design tabs respectively.