Attempt to bump Artifactory plugin, but from Maven Central

The latest known version on Gradle Plugin Portal (which plugins DSL
uses) is 4.21.0.

But it seems newer versions exist that have been deployed on Maven
Central (which makes sense, since GPP was backed by Bintray, which has
now been sunset).

The latest version on Maven Central is 4.24.5 and it seems there have
been fixes around response parsing errors when deploying artifacts,
which have been encountered in recent deployments.

build.gradle

@@ -22,6 +22,7 @@ buildscript {
 	}
 	dependencies {
 		classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlinVersion}"
+		classpath "org.jfrog.buildinfo:build-info-extractor-gradle:4.24.5" //applied in individual submodules
 	}
 }
 
@@ -34,7 +35,7 @@ plugins {
 	id "de.undercouch.download" version "3.4.3"
 	id "org.unbroken-dome.test-sets" version "3.0.0" apply false
 	//note: build scan plugin now must be applied in settings.gradle
-	id "com.jfrog.artifactory" version "4.15.2" apply false
+	//plugin portal is now outdated due to bintray sunset, at least for artifactory gradle plugin
 	id 'biz.aQute.bnd.builder' version '5.0.1' apply false
 	id 'io.spring.nohttp' version '0.0.5.RELEASE'
 	id "io.github.reyerizo.gradle.jcstress" version "0.8.11" apply false