Package fails to install on rsconnect/packrat due to roxygen2 build-time dependency

[karmatarap]

The mcpr package fails to install in rsconnect/packrat deployment environments because it requires roxygen2 to be available at build time, but packrat hasn't installed roxygen2 yet when it tries to build
mcpr.

Error Message

Error in loadNamespace(j <- i[[1L]], c(lib.loc, .libPaths()), versionCheck = vI[[j]]) :
there is no package called 'roxygen2'
Calls: ... loadNamespace -> withRestarts -> withOneRestart -> doWithOneRestart
Execution halted
ERROR: lazy loading failed for package 'mcpr'