Cannot find new versions for dependencies in `allprojects`

Not sure if the title is right. I have the following in my main build.gradle file:

plugins {
	id 'checkstyle'
}

allprojects {
	apply plugin: 'checkstyle'

	dependencies {
		checkstyle 'com.puppycrawl.tools:checkstyle:8.23'
	}
}

Running gradle dependencyUpdates leads to:

Failed to determine the latest version for the following dependencies (use --info for details):
 - com.puppycrawl.tools:checkstyle
     8.23

Not sure why. Any ideas?

[ben-manes]

Good, just wanted to be sure. You need to specify repositories in the all projects block, too.

[boris-petrov]

OK, fair enough. Thank you for the great support! I’ll leave you to decide whether to close the issue or leave it as a reference. Thanks again!