resource/aws_network_acl: Make action in ingress / egress case insensitive

[stack72]

Fixes: #918

Add a diff suppress func to stop case sensitivity issues on the Action
param of ingress and egress. To do this, I had to make sure that the
hash always used the lowercase version (this will mean that users who do
not see a perpetual diff are not affected)

% make testacc TEST=./aws TESTARGS='-run=TestAccAWSNetworkAcl_'                                                               ✹ ✭
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./aws -v -run=TestAccAWSNetworkAcl_ -timeout 120m
=== RUN   TestAccAWSNetworkAcl_importBasic
--- PASS: TestAccAWSNetworkAcl_importBasic (51.69s)
=== RUN   TestAccAWSNetworkAcl_EgressAndIngressRules
--- PASS: TestAccAWSNetworkAcl_EgressAndIngressRules (49.22s)
=== RUN   TestAccAWSNetworkAcl_OnlyIngressRules_basic
--- PASS: TestAccAWSNetworkAcl_OnlyIngressRules_basic (61.61s)
=== RUN   TestAccAWSNetworkAcl_OnlyIngressRules_update
--- PASS: TestAccAWSNetworkAcl_OnlyIngressRules_update (91.95s)
=== RUN   TestAccAWSNetworkAcl_CaseSensitivityNoChanges
--- PASS: TestAccAWSNetworkAcl_CaseSensitivityNoChanges (57.69s)
=== RUN   TestAccAWSNetworkAcl_OnlyEgressRules
--- PASS: TestAccAWSNetworkAcl_OnlyEgressRules (60.46s)
=== RUN   TestAccAWSNetworkAcl_SubnetChange
--- PASS: TestAccAWSNetworkAcl_SubnetChange (92.92s)
=== RUN   TestAccAWSNetworkAcl_Subnets
--- PASS: TestAccAWSNetworkAcl_Subnets (108.76s)
=== RUN   TestAccAWSNetworkAcl_ipv6Rules
--- PASS: TestAccAWSNetworkAcl_ipv6Rules (99.07s)
=== RUN   TestAccAWSNetworkAcl_ipv6VpcRules
--- PASS: TestAccAWSNetworkAcl_ipv6VpcRules (37.64s)
=== RUN   TestAccAWSNetworkAcl_espProtocol
--- PASS: TestAccAWSNetworkAcl_espProtocol (57.23s)
PASS
ok  	github.com/terraform-providers/terraform-provider-aws/aws	768.271s

[grubernaut]

LGTM, one minor comment/improvement

[grubernaut]

This diff suppress is fairly common. Worth splitting it out into a core level function?

[stack72]

I agree it's common - one thing i saw in the committers channel the other day is that sometimes it's preferred to copy small pieces of code like this rather than need to vendor them - thoughts?

[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!