Exclude should occur before missing time check

[billdenney]

library(PKNCA)
#> 
#> Attaching package: 'PKNCA'
#> The following object is masked from 'package:stats':
#> 
#>     filter

d <- data.frame(time = c(1, NA), conc = c(1, NA), exclude = c(NA, "foo"))
PKNCAconc(conc~time, data = d, exclude = "exclude")
#> Error in assert_time(time, sorted_time = sorted_time): Assertion on 'time' failed: Contains missing values (element 2).

^{Created on 2024-07-24 with reprex v2.1.0}