Bug with native `geom_boxplot` with `fill` with stats

[lz100]

Dear Alboukadel,

Thank you for developing this very useful package. I found a buggy behavior when plot boxplot with fill

library(ggpubr)
library(rstatix)

stat.test <- ToothGrowth %>% t_test(len  ~ supp) %>% 
    add_xy_position(x = "supp")

# error `Error in FUN(X[[i]], ...) : object 'supp' not found`
ggplot(ToothGrowth, aes(x = supp, y = len, fill = supp)) +
    geom_boxplot() +
    stat_pvalue_manual(stat.test)

# this will work, without `fill`
ggplot(ToothGrowth, aes(x = supp, y = len)) +
    geom_boxplot() +
    stat_pvalue_manual(stat.test)

# to use fill, I have to use this
ggboxplot(ToothGrowth, x = "supp", y = "len", fill = "supp") + 
    stat_pvalue_manual(stat.test)

R version 4.1.2 (2021-11-01)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Rocky Linux 8.5 (Green Obsidian)

Matrix products: default
BLAS:   /bigdata/operations/pkgadmin/opt/linux/centos/8.x/x86_64/pkgs/R/4.1.2/lib64/R/lib/libRblas.so
LAPACK: /bigdata/operations/pkgadmin/opt/linux/centos/8.x/x86_64/pkgs/R/4.1.2/lib64/R/lib/libRlapack.so

locale:
 [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=en_US.UTF-8        LC_COLLATE=en_US.UTF-8     LC_MONETARY=en_US.UTF-8    LC_MESSAGES=en_US.UTF-8   
 [7] LC_PAPER=en_US.UTF-8       LC_NAME=C                  LC_ADDRESS=C               LC_TELEPHONE=C             LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C       

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] rstatix_0.7.0    ggsignif_0.6.3   ggpubr_0.4.0     hrbrthemes_0.8.0 ggplot2_3.3.5    readr_2.1.2      dplyr_1.0.8      callr_3.7.0      spsUtil_0.2.0    magrittr_2.0.3  
[11] stringr_1.4.0    fs_1.5.2         glue_1.6.1      

loaded via a namespace (and not attached):
 [1] Rcpp_1.0.8         tidyr_1.2.0        ps_1.6.0           assertthat_0.2.1   digest_0.6.29      utf8_1.2.2         R6_2.5.1           backports_1.4.1    evaluate_0.15     
[10] httr_1.4.2         pillar_1.7.0       ggfun_0.0.6        yulab.utils_0.0.4  gdtools_0.2.3      rlang_1.0.2        rstudioapi_0.13    car_3.0-12         extrafontdb_1.0   
[19] DT_0.20            rmarkdown_2.14     labeling_0.4.2     extrafont_0.17     htmlwidgets_1.5.4  munsell_0.5.0      broom_0.7.12       compiler_4.1.2     xfun_0.31         
[28] pkgconfig_2.0.3    systemfonts_1.0.3  gridGraphics_0.5-1 htmltools_0.5.2    tidyselect_1.1.1   tibble_3.1.6       fansi_1.0.2        crayon_1.5.1       tzdb_0.2.0        
[37] withr_2.5.0        ggbreak_0.1.0      grid_4.1.2         Rttf2pt1_1.3.10    gtable_0.3.0       lifecycle_1.0.1    DBI_1.1.2          scales_1.2.0       cli_3.2.0         
[46] stringi_1.7.6      carData_3.0-5      farver_2.1.0       ellipsis_0.3.2     generics_0.1.2     vctrs_0.3.8        RColorBrewer_1.1-3 tools_4.1.2        ggplotify_0.1.0   
[55] purrr_0.3.4        hms_1.1.1          processx_3.5.2     abind_1.4-5        fastmap_1.1.0      yaml_2.3.5         colorspace_2.0-3   aplot_0.1.6        knitr_1.39        
[64] patchwork_1.1.1