Pulsar Client Node 1.15.0

What's Changed

• Ignore src/cert.pem by @shibd in https://github.com/apache/pulsar-client-node/pull/425
• Bump master version to v1.15.0-rc.0 by @shibd in https://github.com/apache/pulsar-client-node/pull/424
• fix(ci): Fix CI build failures and improve stability by @shibd in https://github.com/apache/pulsar-client-node/pull/434
• Support custom message router for partitioned topic producer by @BewareMyPower in https://github.com/apache/pulsar-client-node/pull/435
• Support set batchingMaxAllowedSizeInBytes on producer batch configuration by @shibd in https://github.com/apache/pulsar-client-node/pull/436

Full Changelog: https://github.com/apache/pulsar-client-node/compare/v1.14.0...v1.15.0