Fix failing tests (windows)

[sbuis]

see https://github.com/SticsRPacks/SticsRTests/actions/runs/19925457085/job/57124022087

[plecharpent]

• On Windows, testthat 3.18 installation is failing
  ERROR: dependency 'ellipsis' is not available for package 'testthat'
  => replaced with a simple testthat install: errors in some tests
  see: https://github.com/SticsRPacks/SticsRTests/actions/runs/19235843530/job/54985411938#logs
  **TODO: ** try to identify the problems in some tests

[sbuis]

A problem linked with the tests dedicated to simulation of rotations has been solved (see 2c31c96).

[sbuis]

Remaining tasks:

• re-enable Windows tests in the GitHub action (25cee38)

See also: #22

[sbuis]

Tests on windows and Ubuntu crash due to a problem with testthat.
That is why testthat 3.1.8 was installed at the time.

testthat 3.1.8 was reinstalled (d83cec0)
Manual installation of ellipsis was required (7ac4328)

Now we have error messages linked with the use of our packages (see https://github.com/SticsRPacks/SticsRTests/actions/runs/20958861737/job/60230321703?pr=23)

[vrahier]

The error occurs when following the tutorial during the intercrop-6 chunk (see screenshot below).

By looking into the CroPlotR code, the problematic part seems to be
sim %>% dplyr::select(-tidyselect::any_of(rem_vars)) %>% ….
The error appears to originate around lines 337–344 of cropr_formatting.R in CroPlotR:

  df <-
    sim %>%
    dplyr::select(-tidyselect::any_of(rem_vars)) %>%
    reshape2::melt(
      id.vars = melt_vars_sim,
      na.rm = TRUE,
      value.name = "Simulated"
    )

We need to investigate if sim is NULL at this point.

[sbuis]

Comes from the bug of SticsRFiles on intercrop (main branch) described in SticsRPacks/SticsRFiles#228

=> test refacto branch of CroPlotR with release of other packages (manual test). Does not work because SticsRTest has been adapted to main branch of CroptimizR.