I have the same issue. I was able to get my package to download via

repositories {
	// https://stackoverflow.com/questions/59413364/upgrading-from-gradle-5-1-1-to-6-0-1-breaks-kotlin-multiplatform-build
	jcenter {
		metadataSources {
			gradleMetadata()
			mavenPom()
		}
	}
	jcenter()
}

dependencies {
	add("commonMainApi", "com.github.glwithu06.semver:semver:1.0.1")
}

but I cannot resolve it in my code, it's like it's not on the classpath
I also tried using

plugins {
	java
}

dependencies {
	implementation("com.github.glwithu06.semver:semver:1.0.1")
}

but does not even add it to my external dependencies (although it's downloaded and it's in my modules-2 gradle cache folder along with sources jar, main jar and pom.xml

any ideas?