Test failures for get_study_org and get_isa_investigation

[sneumann]

Hi,
the tests expect_true(tibble::is_tibble(get_study_org('MTBLS375')))
and expect_true(is.character(get_isa_investigation('MTBLS375'))) fail
without the MTBLS_API_KEY variable set, although the tests say 'tokenless-get-methods.
This also causes failures when installing metabolighteR as dependency.
The get_study_org() is setting the key in the function:

metabolighteR/R/get_study_org.R

Line 21 in 22f03fe

httr::add_headers(user_token = getOption('MTBLS_API_KEY'))

while e.g. get_study_desc() does not

metabolighteR/R/get_studies.R

Line 12 in 22f03fe

httr::GET(paste0(getOption('BASE_URL'), '/studies')) %>% httr::content('parsed')

Either the tests or the code seem to need fixing.
Yours, Steffen