It explicitly says, "you can use your action to activate an aura of sunlight". However, it also says, "You emit bright light in a 60-foot radius and dim light 30 feet beyond that." That seems to imply it is just normal light (like the spell daylight) and not sunlight.
Yes, it is considered sunlight
Note that fifth edition is written with standard English in mind and to that end the wording "an aura of sunlight" is an explicit statement that Corona of Light creates sunlight. There is no flavor text in dnd-5e. End of question, there's your answer.
Think that's not enough? There is even a now unofficial ruling (a tweet) from lead game designer Jeremy Crawford:
The daylight spell doesn't create sunlight. Contrast it to the cleric's Corona of Light and the sun blade.
Or for more support, let's compare the Cleric feature to the spells sunbeam and sunburst:
The description of the Corona of Light feature says:
Starting at 17th level, you can use your action to activate an aura of sunlight that lasts for 1 minute or until you dismiss it using another action. You emit bright light in a 60-foot radius and dim light 30 feet beyond that. Your enemies in the bright light have disadvantage on saving throws against any spell that deals fire or radiant damage.
The sunbeam spell description says:
A beam of brilliant light flashes out from your hand in a 5-foot-wide, 60-foot-line. Each creature in the line must make a Constitution saving throw. On a failed save, a creature takes 6d8 radiant damage and is blinded until your next turn. On a successful save, it takes half as much damage and isn't blinded by this spell. Undead and oozes have disadvantage on this saving throw.
You can create a new line of radiance as your action on any turn until the spell ends.
For the duration, a mote of brilliant radiance shines in your hand. It sheds bright light in a 30-foot radius and dim light for an additional 30 feet. The light is sunlight.
The sunburst spell description says:
Brilliant sunlight flashes in a 60-foot radius centered on a point you choose within range. Each creature in that light must make a Constitution saving throw. On a failed save, a creature takes 12d6 radiant damage and is blinded for 1 minute. On a successful save, it takes half as much damage and isn't blinded by this spell. Undead and oozes have disadvantage on this saving throw.
A creature blinded by this spell makes another Constitution saving throw at the end of each of its turns. On a successful save, it is no longer blinded.
This spell dispels any darkness in its area that was created by a spell.
We see from sunbeam that sunlight can be described as shedding bright/dim light. And we see from sunburst that something being sunlight does not have to be explicitly stated in a separate sentence as it is with sunbeam1; it can simply mention sunlight inline as part of its description. Thus, Corona of Light also counts as sunlight in the same way that these two spells do.
For further support, the question "Does the Holy Nimbus emanate actual sunlight?" currently has a well upvoted answer saying the Holy Nimbus feature does count as sunlight despite only including the following relevant text:
[...] Brilliant sunlight flashes in a 60' radius [...]
1 Evidence that sunburst creates sunlight besides standard English:
There exists this well upvoted answer to the question "Does the Daylight spell hurt Vampires?" which assumes that sunburst does create sunlight. Though something being commonly assumed doesn't give it much traction, it is still worth pointing out.