Revert incorrect instance types, keep only c6gd.metal and typo fixes

Co-authored-by: wata727 <9624059+wata727@users.noreply.github.com>

Author: Copilot

rules/aws_db_instance_invalid_type.go

@@ -23,22 +23,6 @@ func NewAwsDBInstanceInvalidTypeRule() *AwsDBInstanceInvalidTypeRule {
 		resourceType:  "aws_db_instance",
 		attributeName: "instance_class",
 		instanceTypes: map[string]bool{
-			"db.c5.24xlarge":            true,
-			"db.c5.18xlarge":            true,
-			"db.c5.12xlarge":            true,
-			"db.c5.9xlarge":             true,
-			"db.c5.4xlarge":             true,
-			"db.c5.2xlarge":             true,
-			"db.c5.xlarge":              true,
-			"db.c5.large":               true,
-			"db.c6g.16xlarge":           true,
-			"db.c6g.12xlarge":           true,
-			"db.c6g.8xlarge":            true,
-			"db.c6g.4xlarge":            true,
-			"db.c6g.2xlarge":            true,
-			"db.c6g.xlarge":             true,
-			"db.c6g.large":              true,
-			"db.c6g.medium":             true,
 			"db.c6gd.metal":             true,
 			"db.c6gd.16xlarge":          true,
 			"db.c6gd.12xlarge":          true,
@@ -48,14 +32,6 @@ func NewAwsDBInstanceInvalidTypeRule() *AwsDBInstanceInvalidTypeRule {
 			"db.c6gd.xlarge":            true,
 			"db.c6gd.large":             true,
 			"db.c6gd.medium":            true,
-			"db.c7g.16xlarge":           true,
-			"db.c7g.12xlarge":           true,
-			"db.c7g.8xlarge":            true,
-			"db.c7g.4xlarge":            true,
-			"db.c7g.2xlarge":            true,
-			"db.c7g.xlarge":             true,
-			"db.c7g.large":              true,
-			"db.c7g.medium":             true,
 			"db.cr1.8xlarge":            true,
 			"db.cv11.18xlarge":          true,
 			"db.cv11.9xlarge":           true,
@@ -338,19 +314,6 @@ func NewAwsDBInstanceInvalidTypeRule() *AwsDBInstanceInvalidTypeRule {
 			"db.rv11.2xlarge":           true,
 			"db.rv11.xlarge":            true,
 			"db.rv11.large":             true,
-			"db.i3.16xlarge":            true,
-			"db.i3.8xlarge":             true,
-			"db.i3.4xlarge":             true,
-			"db.i3.2xlarge":             true,
-			"db.i3.xlarge":              true,
-			"db.i3.large":               true,
-			"db.i4i.32xlarge":           true,
-			"db.i4i.16xlarge":           true,
-			"db.i4i.8xlarge":            true,
-			"db.i4i.4xlarge":            true,
-			"db.i4i.2xlarge":            true,
-			"db.i4i.xlarge":             true,
-			"db.i4i.large":              true,
 			"db.t1.micro":               true,
 			"db.t2.2xlarge":             true,
 			"db.t2.xlarge":              true,

rules/aws_db_instance_invalid_type_test.go

@@ -36,62 +36,6 @@ resource "aws_db_instance" "mysql" {
 			Content: `
 resource "aws_db_instance" "mysql" {
     instance_class = "db.m4.2xlarge"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.c5.large is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.c5.large"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.c6g.16xlarge is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.c6g.16xlarge"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.c7g.medium is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.c7g.medium"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.i3.xlarge is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.i3.xlarge"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.i4i.32xlarge is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.i4i.32xlarge"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.c6gd.metal is valid",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.c6gd.metal"
-}`,
-			Expected: helper.Issues{},
-		},
-		{
-			Name: "db.x2idn.16xlarge is valid (typo fixed)",
-			Content: `
-resource "aws_db_instance" "mysql" {
-    instance_class = "db.x2idn.16xlarge"
 }`,
 			Expected: helper.Issues{},
 		},