Allow use of T2 unlimited by adding appropriate request for the instance

builder/amazon/common/step_run_source_instance.go

@@ -24,6 +24,7 @@ type StepRunSourceInstance struct {
 	Ctx                               interpolate.Context
 	Debug                             bool
 	EbsOptimized                      bool
+	EnableT2Unlimited                 bool
 	ExpectedRootDevice                string
 	IamInstanceProfile                string
 	InstanceInitiatedShutdownBehavior string
@@ -116,6 +117,11 @@ func (s *StepRunSourceInstance) Run(ctx context.Context, state multistep.StateBa
 		EbsOptimized:        &s.EbsOptimized,
 	}
 
+	if s.EnableT2Unlimited {
+		creditOption := "unlimited"
+		runOpts.CreditSpecification = &ec2.CreditSpecificationRequest{CpuCredits: &creditOption}
+	}
+
 	// Collect tags for tagging on resource creation
 	var tagSpecs []*ec2.TagSpecification