chore: fix maven endpoint for cli-lib-alpha (#75)

This package is published to the AWS repository.

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Author: iliapolo

.github/workflows/release.yml

@@ -877,6 +877,7 @@ new JsiiBuild(cliLib, {
     javaPackage: 'software.amazon.awscdk.cli.lib.alpha',
     mavenGroupId: 'software.amazon.awscdk',
     mavenArtifactId: 'cdk-cli-lib-alpha',
+    mavenEndpoint: 'https://aws.oss.sonatype.org',
   },
   publishToPypi: {
     distName: 'aws-cdk.cli-lib-alpha',