make critical_power() and critical_speed() more flexible so it accepts data with more columns

[fmmattioni]

Right now, if the data passed onto critical_power() and critical_speed() has more columns than the ones needed for the function, it will throw an error:

library(cyclingtools)
library(dplyr)

df <- demo_critical_power %>% 
  mutate(additional_column = 0)

df
#> # A tibble: 5 × 3
#>      PO   TTE additional_column
#>   <int> <int>             <dbl>
#> 1   446   100                 0
#> 2   385   172                 0
#> 3   324   434                 0
#> 4   290   857                 0
#> 5   280  1361                 0
  
critical_power(
  .data = df, 
  power_output_column = "PO", 
  time_to_exhaustion_column = "TTE", 
  method = c("3-hyp", "2-hyp", "linear", "1/time"), 
  plot = TRUE, 
  all_combinations = FALSE,
  reverse_y_axis = FALSE
)
#> Error: It looks like the column names you specified do not exist.

^{Created on 2022-02-22 by the reprex package (v2.0.1)}