GHA: "063-superzip-example" test app does not load

[MadhulikaTanuboddi]

This app started failing in the week of April 19 (probably since Friday) in GHA on all builds . https://github.com/rstudio/shinycoreci-apps/runs/2436160314?check_suite_focus=true#step:31:13028

Logs:

2021-04-27T08:35:03.4807180Z [62/368; 7m;32m] 063-superzip-example ~ shinytest.R
2021-04-27T08:35:04.2570430Z Loading required package: shiny
2021-04-27T08:35:17.9880230Z Running mytest.R Error in shinytest.R
2021-04-27T08:35:18.0106980Z ##[error]Error: Shiny app did not load in 10000ms.
2021-04-27T08:35:18.0209270Z S/I 08:35:07.00 window.shinytest loaded
2021-04-27T08:35:18.0268550Z S/I 08:35:07.00 waiting for shiny session to connect
2021-04-27T08:35:18.0269620Z B/I 08:35:07.37 Shiny version:  1.6.0.9000 (:)
2021-04-27T08:35:18.0271610Z B/W 08:35:07.54 TypeError: undefined is not an object (evaluating 'H.normalCall')
2021-04-27T08:35:18.0272950Z   k (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0274600Z B/W 08:35:07.54 TypeError: undefined is not an object (evaluating 've.normalCall')
2021-04-27T08:35:18.0275780Z   Z (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0277450Z B/W 08:35:07.72 TypeError: undefined is not an object (evaluating 'this.lastSentValues[i]')
2021-04-27T08:35:18.0278890Z   setInput (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0280180Z   setInput (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0281370Z   $doSetInput (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0282540Z   immediateCall (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0284160Z   setInput (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0285340Z   setInput (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0288450Z   E (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0289590Z   (anonymous function) (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0290720Z   $invoke (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0291860Z   (anonymous function) (http://127.0.0.1:5741/shared/shiny.min.js:1)
2021-04-27T08:35:18.0293460Z C/E ----------- Loading required package: shiny
2021-04-27T08:35:18.0295060Z C/E ----------- Running application in test mode.
2021-04-27T08:35:18.0386120Z 
2021-04-27T08:35:18.0387900Z C/E ----------- 

I ran the app locally and it does not load. Below is a snapshot of console errors

Note: I have the latest version of leaflet package (2.0.4.1)