Backport (v1.16): in_tail: Manage tail watchers that are rorate_wait state too (#4334)

[daipom]

• in_tail: Manage tail watchers that are rorate_wait state too #4334

[ashie]

Hmm, it would be better to disable CI on Ruby head (by another PR) since it's never succeeded anymore.

[daipom]

Oh, this is not included in v1.16 branch!

• Refine CI #4380

We should backport this, right?

[ashie]

Oh, this is not included in v1.16 branch!

* [WIP: Refine CI #4380](https://github.com/fluent/fluentd/pull/4380)

We should backport this, right?

Yup

[ashie]

https://github.com/fluent/fluentd/actions/runs/8201645424/job/22430795800?pr=4427

Failure: test_unwatched_files_should_be_removed(TailInputTest::path)
/Users/runner/work/fluentd/fluentd/test/plugin/test_in_tail.rb:1616:in `test_unwatched_files_should_be_removed'
     1613:       waiting(20) { sleep 0.1 until Dir.glob("#{@tmp_dir}/*.txt").size == 0 } # Ensure file is deleted on Windows
     1614:       waiting(5) { sleep 0.1 until d.instance.instance_variable_get(:@tails).keys.size <= 0 }
     1615: 
  => 1616:       assert_equal(
     1617:         {
     1618:           files: [],
     1619:           tails: []
<{:files=>[], :tails=>[]}> expected but was
<{:files=>[],
 :tails=>
  ["/Users/runner/work/fluentd/fluentd/test/plugin/../tmp/tail/66f4dcae3574f5b5df9d/tail.txt"]}>

diff:
? {:files=>[], :tails=>[]}
+  :tails=>
+   ["/Users/runner/work/fluentd/fluentd/test/plugin/../tmp/tail/66f4dcae3574f5b5df9d/tail.txt"]}

It seems that sometimes it occurs only on macOS.
It's not concerned with this PR.
e.g.) https://github.com/fluent/fluentd/actions/runs/8166136702/job/22324397018
We need to investigate it later.