fix broken link to helm chart repository reference doc (#317)

Signed-off-by: Kevin Gentile <[email protected]>

README.md

@@ -6,7 +6,7 @@
 
 <p align="center"><img align="center" src="logo2.png"></p><br/>
 
-*ChartMuseum* is an open-source **[Helm Chart Repository](https://github.com/helm/helm-www/blob/master/content/docs/topics/chart_repository.md)** server written in Go (Golang), with support for cloud storage backends, including [Google Cloud Storage](https://cloud.google.com/storage/), [Amazon S3](https://aws.amazon.com/s3/), [Microsoft Azure Blob Storage](https://azure.microsoft.com/en-us/services/storage/blobs/), [Alibaba Cloud OSS Storage](https://www.alibabacloud.com/product/oss), [Openstack Object Storage](https://developer.openstack.org/api-ref/object-store/), [Oracle Cloud Infrastructure Object Storage](https://cloud.oracle.com/storage), [Baidu Cloud BOS Storage](https://cloud.baidu.com/product/bos.html), [Tencent Cloud Object Storage](https://intl.cloud.tencent.com/product/cos), [Netease Cloud NOS Storage](https://www.163yun.com/product/nos), [DigitalOcean Spaces](https://www.digitalocean.com/products/spaces/), [Minio](https://min.io/), and [etcd](https://etcd.io/).
+*ChartMuseum* is an open-source **[Helm Chart Repository](https://helm.sh/docs/topics/chart_repository/)** server written in Go (Golang), with support for cloud storage backends, including [Google Cloud Storage](https://cloud.google.com/storage/), [Amazon S3](https://aws.amazon.com/s3/), [Microsoft Azure Blob Storage](https://azure.microsoft.com/en-us/services/storage/blobs/), [Alibaba Cloud OSS Storage](https://www.alibabacloud.com/product/oss), [Openstack Object Storage](https://developer.openstack.org/api-ref/object-store/), [Oracle Cloud Infrastructure Object Storage](https://cloud.oracle.com/storage), [Baidu Cloud BOS Storage](https://cloud.baidu.com/product/bos.html), [Tencent Cloud Object Storage](https://intl.cloud.tencent.com/product/cos), [Netease Cloud NOS Storage](https://www.163yun.com/product/nos), [DigitalOcean Spaces](https://www.digitalocean.com/products/spaces/), [Minio](https://min.io/), and [etcd](https://etcd.io/).
 
 Works as a valid Helm Chart Repository, and also provides an API for uploading charts.