add convert oml dataset to mlr3

[bakopyan]

[lintr-bot]

tests/testthat/test_local_convertOMLSplitsToMlr3.R:12:40: style: Only use double-quotes.

​      task$input$estimation.procedure[['type']]= oml.types[i]
                                       ^~~~~~

tests/testthat/test_local_convertOMLSplitsToMlr3.R:12:48: style: Put spaces around all infix operators (except exponentiation).

​      task$input$estimation.procedure[['type']]= oml.types[i]
                                              ~^