How can you tell?

That article is just a quote from their company profile, followed by the output of a program that compares current valuation to historical average, turned into sentences, probably using one of a few templates.
The images, though quite nice, are automatically generated for all the stocks they cover.

It isn't exactly a big reach to guess that it's automatically written. The great majority of financial "news" articles in "news" feeds are written by bots, and have been for some years now. Zacks was an early mover. ("Dollar General (DG) Stock Moves -0.63%: What You Should Know..."). So these days it's better to assume it's written by a bot, but then look for anything at all that seems to show a human thought about it to see if it's an exception. This article has nothing like that. At best, someone gave it a once-over for plausibility before pushing it out.

Some articles have dead giveaways, like "Quarterly revenue rose by 0.003% compared to the same quarter last year". A human would just say revenue was flat.
The templates they use are getting better, though, so you don't see crazy stuff like that quite as often. It's easier to be fooled into thinking there was thinking behind what was written.

An example of a bot-written article.
finance.yahoo.com - Dollar general dg stock moves

From the same template:
CVS Health (CVS) closed at $53.87 in the latest trading session, marking a -1.86% move from the prior day. This change lagged the S&P 500's...
DocuSign (DOCU) closed at $52.06 in the latest trading session, marking a +0.66% move from the prior day...
FedEx (FDX) closed at $226.33 in the latest trading session, marking a -1.01% move from the prior day. This change lagged the S&P 500's...
Palo Alto Networks (PANW) closed at $134.19 in the latest trading session, marking a -0.66% move from the prior day...
Union Pacific (UNP) closed at $202.51 in the latest trading session, marking a -0.69% move from the prior day. This change was narrower than...
Marathon Oil (MRO) closed at $26.80 in the latest trading session, marking a -1.03% move from the prior day. This move lagged the S&P 500's daily loss of...

Jim