Layout/LineLength splits improperly when a send node has a heredoc argument

[dvandersluis]

Extracted from #9749 (comment) by @gregnavis

I'd like to report a similar problem with method calls and heredocs.

In my case, the following method definition:

 def test_unindexed_foreign_keys
   assert_equal(<<~OUTPUT, unindexed_foreign_keys({ "users" => ["profile_id", "account_id"], "account" => ["group_id"] >}))
     account group_id
     users account_id profile_id
   OUTPUT
 end

gets transformed into

 def test_unindexed_foreign_keys
   assert_equal(<<~OUTPUT, 
unindexed_foreign_keys({ "users" => ["profile_id", "account_id"], "account" => ["group_id"] }))
     account group_id
     users account_id profile_id
   OUTPUT
 end

You can see the original method invoked assert_equal with two arguments, the first one defined as a heredoc. The transformed method is syntactically invalid as the second argument and the following closing parenthesis were moved into the heredoc.