fix(discover): Pick the correct y-axis for unfurls

[shruthilayaj]

We have some Discover Saved queries that don't have
yAxis saved on the Database. To avoid yAxis mix ups
when these links are shared, we just want to mimic
how Discover displays yAxis - picking the first option
when yAxis isn't explicitly specified.

[wmak]

nit:
could either do
faster but messy

Suggested change

	def is_aggregate(field: str) -> bool:
	field_match = re.match(AGGREGATE_PATTERN, field)
	equation_match = re.match(AGGREGATE_BASE, field) and is_equation(field)
	if field_match or equation_match:
	return True
	return False
	def is_aggregate(field: str) -> bool:
	field_match = re.match(AGGREGATE_PATTERN, field)
	if field_match:
	return True
	equation_match = re.match(AGGREGATE_BASE, field) and is_equation(field)
	if equation_match:
	return True
	return False

cleaner:

Suggested change

	def is_aggregate(field: str) -> bool:
	field_match = re.match(AGGREGATE_PATTERN, field)
	equation_match = re.match(AGGREGATE_BASE, field) and is_equation(field)
	if field_match or equation_match:
	return True
	return False
	def is_aggregate(field: str) -> bool:
	field_match = re.match(AGGREGATE_PATTERN, field)
	equation_match = re.match(AGGREGATE_BASE, field) and is_equation(field)
	return (field_match or equation_match) is not None