Fix 3838 - deprecate datanalyzer (#3839)

Co-authored-by: Horacio Sanson <horacio@allm.inc>

test/handler/test_dartanalyzer_handler.vader

@@ -1,28 +0,0 @@
-Before:
-  runtime ale_linters/dart/dartanalyzer.vim
-
-After:
-  call ale#linter#Reset()
-
-Execute(Basic problems should be parsed correctly):
-  AssertEqual
-  \ [
-  \   {
-  \     'type': 'E',
-  \     'text': 'expected_token: Expected to find ''}''',
-  \     'lnum': 5,
-  \     'col': 1,
-  \   },
-  \   {
-  \     'type': 'W',
-  \     'text': 'invalid_assignment: A value of type ''String'' can''t be assigned to a variable of type ''int''',
-  \     'lnum': 2,
-  \     'col': 16,
-  \   },
-  \ ],
-  \ ale_linters#dart#dartanalyzer#Handle(bufnr(''), [
-  \ 'Analyzing main.dart...',
-  \ '  error • Expected to find ''}'' at main.dart:5:1 • expected_token',
-  \ '  warning • A value of type ''String'' can''t be assigned to a variable of type ''int'' at main.dart:2:16 • invalid_assignment',
-  \ '1 error and 1 warning found.',
-  \ ])

test/linter/test_dartanalyzer.vader

@@ -1,20 +0,0 @@
-Before:
-  call ale#assert#SetUpLinterTest('dart', 'dartanalyzer')
-
-After:
-  call ale#assert#TearDownLinterTest()
-
-Execute(The default command and executable should be correct):
-  AssertLinter 'dartanalyzer', ale#Escape('dartanalyzer') . ' %s'
-
-Execute(The executable should be configurable):
-  let g:ale_dart_dartanalyzer_executable = 'foobar'
-
-  AssertLinter 'foobar', ale#Escape('foobar') . ' %s'
-
-Execute(The .packages file should be set if detected):
-  call ale#test#SetFilename('../test-files/dart/foo')
-
-  AssertLinter 'dartanalyzer', ale#Escape('dartanalyzer')
-  \   . ' --packages ' . ale#Escape(ale#path#Simplify(g:dir . '/../test-files/dart/.packages'))
-  \ . ' %s'