Amazon Neptune Database now supports R7i instances

[Amazon Neptune Database](https://aws.amazon.com/neptune/) now supports R7i database instances powered by custom 4th Generation Intel Xeon Scalable processors. R7i instances offer larger instance sizes, up to 48xlarge and features an 8:1 ratio of memory to vCPU, and the latest DDR5 memory. These instances are now available in the following AWS Regions: US East (N. Virginia, Ohio), US West (N. California, Oregon), Asia Pacific (Jakarta, Mumbai, Seoul, Singapore, Sydney, Tokyo), Canada (Central), and Europe (Frankfurt, Ireland, London, Paris, Spain, Stockholm), and engine versions 1.4.3 or above. Amazon Neptune is a fast, reliable, fully managed graph database service that makes it easier to build and run applications that work with highly connected datasets. Compared to previous generation R6i instances, the R7i instances deliver up to 15% better price performance, powering your graph use cases such as fraud graphs, knowledge graphs, customer 360 graphs, and security graphs. You can launch R7i instances for Neptune using the [AWS Management Console](https://console.aws.amazon.com/neptune/) or using the [AWS CLI](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/neptune/index.html). Upgrading a Neptune cluster to R7i instances requires a simple instance type modification for Neptune engine versions 1.4.3 or higher. For more information on pricing and regional availability, refer to the [Amazon Neptune pricing page](https://aws.amazon.com/neptune/pricing/).