[ci] [R-package] Add duplicate_argument_linter (#5310)

* Add duplicate_argument_linter

* Add duplicate_argument_linter

* added acomment for duplicate argument

* Update R-package/tests/testthat/test_utils.R
Co-authored-by: José Morales <jmoralz92@gmail.com>
Co-authored-by: José Morales <jmoralz92@gmail.com>

.ci/lint_r_code.R

@@ -36,6 +36,7 @@ LINTERS_TO_USE <- list(
     , "braces"               = lintr::brace_linter()
     , "class_equals_linter"  = lintr::class_equals_linter()
     , "commas"               = lintr::commas_linter()
+    , "duplicate_argument"   = lintr::duplicate_argument_linter()
     , "equals_na"            = lintr::equals_na_linter()
     , "function_left"        = lintr::function_left_parentheses_linter()
     , "implicit_integers"    = lintr::implicit_integer_linter()

R-package/tests/testthat/test_utils.R

@@ -29,7 +29,7 @@ test_that("lgb.params2str() passes through duplicated params", {
         params = list(
             objective = "regression"
             , bagging_fraction = 0.8
-            , bagging_fraction = 0.5
+            , bagging_fraction = 0.5  # nolint: duplicate_argument
         )
     )
     expect_equal(out_str, "objective=regression bagging_fraction=0.8 bagging_fraction=0.5")