test_coverage_active_file() fails with testthat 3.3

[jonthegeek]

In testthat 3.3, local_snapshotter() gained a new 1st argument, reporter. The PR acknowledged that local_snapshotter() is used in devtools, but devtools doesn't appear to have an update to deal with the new 1st parameter (and it passes the path unnamed). Therefore, it no longer works:

# I technically had to manually uninstall testthat before this.
devtools::install_version("testthat", "3.2.3")
devtools::test_coverage_active_file()
#> (no error)

pak::pak("testthat")
devtools::test_coverage_active_file()
#> Error in reporter$new : $ operator is invalid for atomic vectors

I'll PR this momentarily.