Remove TODOs related to use of FIPS endpoints with DynamoDB

Decided to keep the current code as-is, so removing the TODOs

aws/aws-sdk-go#5078 was landed upstream, so bump `aws-sdk-go` to pick up the change.
Note that this new functionality is not used, but would like to keep it updated
so it can possibly be used in the future without needing to bump the SDK version.

go.mod

@@ -37,7 +37,7 @@ require (
 	github.com/andybalholm/brotli v1.0.6
 	github.com/aquasecurity/libbpfgo v0.5.1-libbpf-1.2
 	github.com/armon/go-radix v1.0.0
-	github.com/aws/aws-sdk-go v1.49.4
+	github.com/aws/aws-sdk-go v1.49.13
 	github.com/aws/aws-sdk-go-v2 v1.24.0
 	github.com/aws/aws-sdk-go-v2/config v1.26.1
 	github.com/aws/aws-sdk-go-v2/credentials v1.16.12

go.sum

@@ -194,8 +194,8 @@ github.com/aws/aws-lambda-go v1.13.3/go.mod h1:4UKl9IzQMoD+QF79YdCuzCwp8VbmG4VAQ
 github.com/aws/aws-sdk-go v1.17.4/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
 github.com/aws/aws-sdk-go v1.27.0/go.mod h1:KmX6BPdI08NWTb3/sm4ZGu5ShLoqVDhKgpiN924inxo=
 github.com/aws/aws-sdk-go v1.44.263/go.mod h1:aVsgQcEevwlmQ7qHE9I3h+dtQgpqhFB+i8Phjh7fkwI=
-github.com/aws/aws-sdk-go v1.49.4 h1:qiXsqEeLLhdLgUIyfr5ot+N/dGPWALmtM1SetRmbUlY=
-github.com/aws/aws-sdk-go v1.49.4/go.mod h1:LF8svs817+Nz+DmiMQKTO3ubZ/6IaTpq3TjupRn3Eqk=
+github.com/aws/aws-sdk-go v1.49.13 h1:f4mGztsgnx2dR9r8FQYa9YW/RsKb+N7bgef4UGrOW1Y=
+github.com/aws/aws-sdk-go v1.49.13/go.mod h1:LF8svs817+Nz+DmiMQKTO3ubZ/6IaTpq3TjupRn3Eqk=
 github.com/aws/aws-sdk-go-v2 v0.18.0/go.mod h1:JWVYvqSMppoMJC0x5wdwiImzgXTI9FuZwxzkQq9wy+g=
 github.com/aws/aws-sdk-go-v2 v1.18.0/go.mod h1:uzbQtefpm44goOPmdKyAlXSNcwlRgF3ePWVW6EtJvvw=
 github.com/aws/aws-sdk-go-v2 v1.24.0 h1:890+mqQ+hTpNuw0gGP6/4akolQkSToDJgHfQE7AwGuk=

lib/backend/dynamo/dynamodbbk.go

@@ -275,13 +275,11 @@ func New(ctx context.Context, params backend.Params) (*Backend, error) {
 	}
 	b.session.Config.HTTPClient = httpClient
 
-	// create DynamoDB service:
+	// Create DynamoDB service.
 	svc, err := dynamometrics.NewAPIMetrics(dynamometrics.Backend, dynamodb.New(b.session, &aws.Config{
 		// Setting this on the individual service instead of the session, as DynamoDB Streams
 		// and Application Auto Scaling do not yet have FIPS endpoints in non-GovCloud.
 		// See also: https://aws.amazon.com/compliance/fips/#FIPS_Endpoints_by_Service
-		// TODO(reed): This can be simplified once https://github.com/aws/aws-sdk-go/pull/5078
-		// is available (or whenever AWS adds the missing FIPS endpoints).
 		UseFIPSEndpoint: useFIPSEndpoint,
 	}))
 	if err != nil {

lib/events/dynamoevents/dynamoevents.go

@@ -287,13 +287,11 @@ func New(ctx context.Context, cfg Config) (*Log, error) {
 		return nil, trace.Wrap(err)
 	}
 
-	// create DynamoDB service:
+	// Create DynamoDB service.
 	svc, err := dynamometrics.NewAPIMetrics(dynamometrics.Events, dynamodb.New(b.session, &aws.Config{
 		// Setting this on the individual service instead of the session, as DynamoDB Streams
 		// and Application Auto Scaling do not yet have FIPS endpoints in non-GovCloud.
 		// See also: https://aws.amazon.com/compliance/fips/#FIPS_Endpoints_by_Service
-		// TODO(reed): This can be simplified once https://github.com/aws/aws-sdk-go/pull/5078
-		// is available (or whenever AWS adds the missing FIPS endpoints).
 		UseFIPSEndpoint: events.FIPSProtoStateToAWSState(cfg.UseFIPSEndpoint),
 	}))
 	if err != nil {