I'm playing a 10th-level artillerist artificer for a one-shot my friend is running, and while playtesting some with another friend (so I could actually learn my character sheet), she cast Dispel Magic on my summoned turret. I thought the turret shouldn't be affected, she thought it should be rendered inert.
For reference, the feature of the revised 2019 artificer on D&DBeyond has the following text:

At 3rd level, you learn how to create a magical turret. With your smith’s tools in hand, you can take an action to magically summon a Medium turret in an unoccupied space on a horizontal surface within 5 feet of you.

It does also say that "the turret is a magical object". From Does dispel magic work on magical weapons? I feel like Dispel Magic shouldn't work on my turret.

Similarly, it shouldn't be able to remove my artificer infusions from any infused items I have, right?

No, dispel magic will not remove the turrets

Arcane Turret says:

At 3rd level you learn how to create a magical turret. With your smith's tools in hand you can take an action to magically summon a Medium turret [...]

So the turrets are magical and are created by taking a specially defined action as part of a class feature. However they are not spells or created by a spell effect.¹

This is important because dispel magic only has any effect on things that are spells:

Choose one creature, object, or magical effect within range. Any spell of 3rd level or lower on the target ends.

Since magical turret is not a spell, dispel magic won't do anything to them (unless they happen to have an unrelated spell on them).

This aligns with guidance from the Sage Advice Compendium:

Can you use dispel magic to dispel a magical effect like a vampire’s
Charm ability or a druid’s Wild Shape?

Dispel magic has a particular purpose: to break other spells. It has
no effect on a vampire’s Charm ability or any other magical effect
that isn’t a spell. It also does nothing to the properties of a magic
item. (SAC v2.3 p 14)

^{1 - You can see this Q&A for an in-depth discussion for what counts as a spell. In short: nowhere does the feature say anything about a spell, or say you "cast" anything, or give this ability a spell name or spell block listed anywhere. Without those things, this can't be a spell.}

Dispel Magic ends spells and nothing else

The description of Dispel Magic states:

Any spell of 3rd level or lower on the target ends.

All the description says is that it ends spells. Further note this question from [Sage Advice]:

Can you use dispel magic to dispel a magical effect like a vampire’s Charm ability or a druid’s Wild Shape?

Dispel magic has a particular purpose: to break other spells. It has no effect on a vampire’s Charm ability or any other magical effect that isn’t a spell. It also does nothing to the proper-ties of a magic item.

This makes it very clear that Dispel Magic only ends spell. Other magical effects are not affected by Dispel Magic, including Infusions and magical turrets.

Since this is the general rule, anything that isn't a spell that is intended to be affected by Dispel Magic has to state so in its description. For example, the Flying Sword monster does specifically state that is affected by Dispel Magic. The turrets and infusions make no such exceptions so are not affected by Dispel Magic