Closes #127: replace `round_sas` by `round_half_up`

[kaz462]

@robertdevine raised a good point for using tidytlg:roundSAS instead of round_sas

Also, the current project level round_sas has this issue, although no impact on pilot3.

janitor::round_half_up has the same functionality as tidytlg:roundSAS, since janitor is already in our renv.lock file, will use janitor::round_half_up to avoid updating the lock file

• No impact on the adsl, qc_adsl.r has the same result as before

[laxamanaj]

Thanks for checking @bms63 . I'll merge.