Fixes issue 2344 empty result for get splits

[JanMkl]

Simple fix for #2344. Checks the current history that it contains the timescale we expect for these functions if not refetch the history.

• Added check in get_history_metadata that if cached metadata doesn't contain trading periods then fetch intra day history.
• Added check that if cached history is not max period then refetch the history for get_dividends, get_capital_gains, get_splits and get_actions.

This pull request can be discarded if the larger rework #2345 is completed.

[JanMkl]

Added some tests for basic validation of the data received from get_history_metadata, get_dividends, get_capital_gains, get_splits and get_actions.

If this PR is decided to be merged I can squash these to a single commit but until then I'll let it be two separate commits as the test could be cherry picked to rework #2345 if/when that is completed.

[dhruvan2006]

@JanMkl I have implemented the caching mechanism in #2345. You can have a gander

[JanMkl]

Closing this as #2345 is merged.

@ValueRaider do you see any value adding the tests on this PR to project? I can open a separate PR for those if you see them as useful.

[dhruvan2006]

There's already a few tests here, maybe you can expand them?

yfinance/tests/test_ticker.py

Lines 318 to 331 in fa3094d

	def test_dividends(self):
	data = self.ticker.dividends
	self.assertIsInstance(data, pd.Series, "data has wrong type")
	self.assertFalse(data.empty, "data is empty")
	def test_splits(self):
	data = self.ticker.splits
	self.assertIsInstance(data, pd.Series, "data has wrong type")
	# self.assertFalse(data.empty, "data is empty")
	def test_actions(self):
	data = self.ticker.actions
	self.assertIsInstance(data, pd.DataFrame, "data has wrong type")
	self.assertFalse(data.empty, "data is empty")