No non-missing arguments to max; returning -Inf

[nanxstats]

Run the following example from ?as_gt()

gs_power_wlr() %>%
  summary() %>%
  as_gt(
    colname_spanner = "Cumulative probability to cross boundaries",
    colname_spannersub = c("under H1", "under H0")
  )

yields the following warning message:

Warning message:
  In max((x %>% dplyr::filter(Bound == display_bound[1]))[[colname_spannersub[2]]]) :
  no non-missing arguments to max; returning -Inf

For this reason, suppressWarnings() had to be used in as_gt() tests in #337 to keep test outputs clean.