Removes the cached WMDA data, causing toSerology to revert
to using the bundled package data.
Examples
# Check if cache exists (safe operation, no side effects)
cache_dir <- file.path(tempdir(), "wmda_cache_test")
# This will report "No WMDA cache found" since we use a temp directory
clearWmdaCache(cache_dir = cache_dir)
#> No WMDA cache found
# \donttest{
# Clear the default WMDA cache
clearWmdaCache()
#> No WMDA cache found
# }
