weights argument fails when using dplyr group_by

[martinamorris]

Example:

df <- data.frame(grp = rbinom(100, 1, .5),
                 var = rnorm(100, 10, 2),
                 wt = abs(rnorm(100)))

df %>% sjmisc::descr(weights = wt) # works

## Basic descriptive statistics

# var    type label  n NA.prc mean   sd   se             range      iqr skew
# grp integer   grp 85      0 0.51 0.50 0.05           1 (0-1) 1.000000 0.08
# var numeric   var 85      0 9.85 1.85 0.18 8.12 (6.41-14.53) 2.550164 0.19

df %>% group_by(grp) %>%           # doesn't work
  sjmisc::descr(weights = wt)

# Error in `[.data.frame`(descr_helper(tmp, max.length), , show) : 
#  undefined columns selected

> sessioninfo::package_info(pkgs = c("sjmisc", "dplyr"))
 package    * version date       lib source        
 assertthat   0.2.1   2019-03-21 [1] CRAN (R 4.0.0)
 cli          2.3.1   2021-02-23 [1] CRAN (R 4.0.4)
 crayon       1.4.1   2021-02-08 [1] CRAN (R 4.0.3)
 digest       0.6.27  2020-10-24 [1] CRAN (R 4.0.3)
 dplyr      * 1.0.4   2021-02-02 [1] CRAN (R 4.0.4)
 ellipsis     0.3.1   2020-05-15 [1] CRAN (R 4.0.0)
 fansi        0.4.2   2021-01-15 [1] CRAN (R 4.0.3)
 generics     0.1.0   2020-10-31 [1] CRAN (R 4.0.3)
 glue         1.4.2   2020-08-27 [1] CRAN (R 4.0.2)
 insight      0.13.1  2021-02-22 [1] CRAN (R 4.0.4)
 lifecycle    1.0.0   2021-02-15 [1] CRAN (R 4.0.4)
 magrittr     2.0.1   2020-11-17 [1] CRAN (R 4.0.3)
 pillar       1.5.1   2021-03-05 [1] CRAN (R 4.0.3)
 pkgconfig    2.0.3   2019-09-22 [1] CRAN (R 4.0.0)
 purrr        0.3.4   2020-04-17 [1] CRAN (R 4.0.0)
 R6           2.5.0   2020-10-28 [1] CRAN (R 4.0.3)
 rlang        0.4.10  2020-12-30 [1] CRAN (R 4.0.3)
 sjlabelled   1.1.7   2020-09-24 [1] CRAN (R 4.0.3)
 sjmisc       2.8.6   2021-01-07 [1] CRAN (R 4.0.3)
 tibble       3.1.0   2021-02-25 [1] CRAN (R 4.0.4)
 tidyselect   1.1.0   2020-05-11 [1] CRAN (R 4.0.0)
 utf8         1.1.4   2018-05-24 [1] CRAN (R 4.0.0)
 vctrs        0.3.6   2020-12-17 [1] CRAN (R 4.0.3)

Not sure you intended for these tools to work with group_by -- but it would be great if they did :)