Add aws overview dashboard

[kaiyan-sheng]

With cloudwatch metricset merged, we can collect a lot of useful metrics from cloudwatch from different namespaces. Here is an example aws overview dashboard which includes metrics from EC2, SQS, S3, ECS, ELB and Lambda:

closes: #11007

[kaiyan-sheng]

For some reason, I can no longer import the dashboard json file after I created #12157. So this PR is to replace it.

[sayden]

I checked locally and it seems some kind of error when trying to load the dashboard

[kaiyan-sheng]

I think I mentioned my question to @exekias @sayden before but I think I should post it here:
I created ECS CPU Available (and ECS Memory Available) in the overview dashboard instead of two separate virtualization: CPUReservation and CPUUtilization. Does it make sense?
Cloudwatch gives CPUReservation and CPUUtilization, as well as MemoryReservation and MemoryUtilization.

ECS CPU Available = ECS CPUReservation - ECS CPUUtilization
CPUReservation: The percentage of CPU units that are reserved by running tasks in the cluster.
CPUUtilization: The percentage of CPU units that are used in the cluster or service.

For example, for one of the cluster I can see, CPUReservation = 0.781(percent) and CPUUtilization = 0.376(percent) from AWS Cloudwatch:

[sayden]

@kaiyan-sheng and me talked shortly about the naming and I also think that the naming and grouping Kaiyan is proposing is perfect

[kaiyan-sheng]

@sayden @exekias I think this one is ready to get in. This suppose to be an example to show users how or what they can do with cloudwatch metricset. It's not suppose to be something user will 100% use for overview with their use case. So my thought is, if no error loading the dashboard, then we can merge it 😬 What do you guys think?

[exekias]

SGTM, as we advance with modules this dashboard could keep evolving to become more of an inventory view linking to detailed dashboards per module

[kaiyan-sheng]

Sounds good to me. I just tested this again and should load just fine.