resource/aws_elb: Return any errors when updating listeners

[bflad]

Closes #3785

Previously, it was ignoring any errors from expandListeners and subsequently skipping the addition of invalid listeners:

make testacc TEST=./aws TESTARGS='-run=TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate -timeout 120m
=== RUN   TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate
--- FAIL: TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate (40.41s)
	testing.go:511: Step 2, expected error:

		After applying this step, the plan was not empty:

		DIFF:

		UPDATE: aws_elb.bar
		  listener.#:                             "1" => "2"
		  listener.1105221442.instance_port:      "443" => "443"
		  listener.1105221442.instance_protocol:  "https" => "https"
		  listener.1105221442.lb_port:            "443" => "443"
		  listener.1105221442.lb_protocol:        "https" => "https"
		  listener.1105221442.ssl_certificate_id: "arn:aws:iam::187416307283:server-certificate/tf-acctest-x09yfu0gci" => "arn:aws:iam::187416307283:server-certificate/tf-acctest-x09yfu0gci"
		  listener.3527251857.instance_port:      "" => "8443"
		  listener.3527251857.instance_protocol:  "" => "tcp"
		  listener.3527251857.lb_port:            "" => "8443"
		  listener.3527251857.lb_protocol:        "" => "tcp"
		  listener.3527251857.ssl_certificate_id: "" => "arn:aws:iam::187416307283:server-certificate/tf-acctest-x09yfu0gci"

...

		To match:

		ssl_certificate_id may be set only when protocol is 'https' or 'ssl'


FAIL
FAIL	github.com/terraform-providers/terraform-provider-aws/aws	40.441s
make: *** [testacc] Error 1

Now passes:

make testacc TEST=./aws TESTARGS='-run=TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate -timeout 120m
=== RUN   TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate
--- PASS: TestAccAWSELB_Listener_SSLCertificateID_IAMServerCertificate (40.59s)
PASS
ok  	github.com/terraform-providers/terraform-provider-aws/aws	40.623s

[katbyte]

LGTM

[bflad]

This has been released in version 1.14.1 of the AWS provider. Please see the Terraform documentation on provider versioning or reach out if you need any assistance upgrading.

[ghost]

I'm going to lock this issue because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active issues.

If you feel this issue should be reopened, we encourage creating a new issue linking back to this one for added context. Thanks!