Shade gradle-plugin dependencies

[sschuberth]

While the gradle-plugin that the gradle-inspector injects into the build via an init.gradle script is already built as a fat JAR, see

ort/plugins/package-managers/gradle-plugin/build.gradle.kts

Lines 60 to 80 in 9607cd0

	tasks.register<Jar>("fatJar") {
	description = "Creates a fat JAR that includes all required runtime dependencies."
	group = "Build"
	archiveClassifier = "fat"
	// Handle duplicate `META-INF/DEPENDENCIES` files.
	duplicatesStrategy = DuplicatesStrategy.EXCLUDE
	from(sourceSets.main.get().output)
	dependsOn(configurations.runtimeClasspath)
	from({
	configurations.runtimeClasspath.get().filter {
	// Only bundle JARs that are not specific to the Gradle version.
	it.extension == "jar" && !("gradle" in it.path && gradle.gradleVersion in it.path)
	}.map {
	zipTree(it)
	}
	})
	}

the bundled dependencies are not rewritten / shaded regarding their package locations. So depending on classpath ordering, e.g. the "wrong" Kotlin standard library could be used, resulting in strange errors like

NoSuchMethodError: 'java.util.List kotlin.collections.CollectionsKt.createListBuilder()'

because the stdlib bundled with Gradle's Kotlin DSL is used instead of the one from the gradle-plugin.

The general problem is a bit similar to #6798.

As a solution, either the Shadow plugin could be used with relocation, or the probably even more fitting Gr8 plugin could be used.