Add support for cache instance families m7g and r7g (#545)

Author: dvxam

rules/aws_elasticache_cluster_previous_type_test.go

@@ -36,6 +36,22 @@ resource "aws_elasticache_cluster" "redis" {
 			Content: `
 resource "aws_elasticache_cluster" "redis" {
     node_type = "cache.t2.micro"
+}`,
+			Expected: helper.Issues{},
+		},
+		{
+			Name: "supports cache.m7g family type",
+			Content: `
+resource "aws_elasticache_cluster" "redis" {
+    node_type = "cache.r7g.large"
+}`,
+			Expected: helper.Issues{},
+		},
+		{
+			Name: "supports cache.r7g family type",
+			Content: `
+resource "aws_elasticache_cluster" "redis" {
+    node_type = "cache.r7g.large"
 }`,
 			Expected: helper.Issues{},
 		},

rules/utils.go

@@ -33,6 +33,13 @@ var validElastiCacheNodeTypes = map[string]bool{
 	"cache.m6g.8xlarge":   true,
 	"cache.m6g.12xlarge":  true,
 	"cache.m6g.16xlarge":  true,
+	"cache.m7g.large":     true,
+	"cache.m7g.xlarge":    true,
+	"cache.m7g.2xlarge":   true,
+	"cache.m7g.4xlarge":   true,
+	"cache.m7g.8xlarge":   true,
+	"cache.m7g.12xlarge":  true,
+	"cache.m7g.16xlarge":  true,
 	"cache.r3.large":      true,
 	"cache.r3.xlarge":     true,
 	"cache.r3.2xlarge":    true,
@@ -63,6 +70,13 @@ var validElastiCacheNodeTypes = map[string]bool{
 	"cache.r6gd.8xlarge":  true,
 	"cache.r6gd.12xlarge": true,
 	"cache.r6gd.16xlarge": true,
+	"cache.r7g.large":     true,
+	"cache.r7g.xlarge":    true,
+	"cache.r7g.2xlarge":   true,
+	"cache.r7g.4xlarge":   true,
+	"cache.r7g.8xlarge":   true,
+	"cache.r7g.12xlarge":  true,
+	"cache.r7g.16xlarge":  true,
 	"cache.m1.small":      true,
 	"cache.m1.medium":     true,
 	"cache.m1.large":      true,