Before:
  runtime ale_linters/robot/rflint.vim

After:
  call ale#linter#Reset()

Execute(Warning and error messages should be handled correctly):
  AssertEqual
  \ [
  \   {
  \     'bufnr': 1,
  \     'filename': 'test.robot',
  \     'type': 'W',
  \     'lnum': 1,
  \     'col': 2,
  \     'text': 'RequireSuiteDocumentation',
  \     'detail': 'No suite documentation',
  \   },
  \   {
  \     'bufnr': 1,
  \     'filename': 'test.robot',
  \     'type': 'E',
  \     'lnum': 3,
  \     'col': 4,
  \     'text': 'RequireTestDocumentation',
  \     'detail': 'No testcase documentation',
  \   },
  \ ],
  \ ale_linters#robot#rflint#Handle(1, [
  \   'test.robot:W:1:2:RequireSuiteDocumentation:No suite documentation',
  \   'test.robot:E:3:4:RequireTestDocumentation:No testcase documentation'
  \])