[#3677] Add on_demand and spot instance count for telemetry

### What is the feature/fix?

https://app.asana.com/0/1203637156732418/1204423756010922/f

### Add screenshot or video (optional)

### Does it has a breaking change?

no

### How to use/test it?

### Checklist
- [ ] New coverage tests
- [ ] Unit tests passing
- [ ] E2E tests passing
- [ ] E2E downgrade/update test passing
- [ ] Documentation updated
- [ ] No warnings or errors on Deepsource/Codecov

provider/aws/workers_heartbeat.go

@@ -1,8 +1,11 @@
 package aws
 
 import (
+	"strings"
 	"time"
 
+	"github.com/aws/aws-sdk-go/aws"
+	"github.com/aws/aws-sdk-go/service/ec2"
 	"github.com/convox/logger"
 	"github.com/convox/rack/pkg/helpers"
 )
@@ -26,15 +29,45 @@ func (p *Provider) heartbeat() {
 		return
 	}
 
+	req := &ec2.DescribeInstancesInput{
+		Filters: []*ec2.Filter{
+			{Name: aws.String("tag:Rack"), Values: []*string{aws.String(p.Rack)}},
+			{Name: aws.String("tag:aws:cloudformation:logical-id"), Values: []*string{aws.String("Instances"), aws.String("SpotInstances")}},
+			{Name: aws.String("instance-state-name"), Values: []*string{aws.String("pending"), aws.String("running"), aws.String("shutting-down"), aws.String("stopping")}},
+		},
+	}
+
+	onDemandCnt := 0
+	spotCnt := 0
+
+	err = p.ec2().DescribeInstancesPages(req, func(res *ec2.DescribeInstancesOutput, last bool) bool {
+		for _, r := range res.Reservations {
+			for _, i := range r.Instances {
+				if i.InstanceLifecycle != nil && strings.ToLower(*i.InstanceLifecycle) == "spot" {
+					spotCnt++
+				} else {
+					onDemandCnt++
+				}
+			}
+		}
+		return true
+	})
+	if err != nil {
+		log.Error(err)
+		return
+	}
+
 	ms := map[string]interface{}{
-		"id":             coalesces(p.ClientId, p.StackId),
-		"app_count":      len(as),
-		"instance_count": s.Count,
-		"instance_type":  s.Type,
-		"provider":       "aws",
-		"rack_id":        p.StackId,
-		"region":         p.Region,
-		"version":        s.Version,
+		"id":                       coalesces(p.ClientId, p.StackId),
+		"app_count":                len(as),
+		"instance_count":           s.Count,
+		"instance_type":            s.Type,
+		"provider":                 "aws",
+		"rack_id":                  p.StackId,
+		"region":                   p.Region,
+		"version":                  s.Version,
+		"on_demand_instance_count": onDemandCnt,
+		"spot_instance_count":      spotCnt,
 	}
 
 	telemetryOn := s.Parameters["Telemetry"] == "true"