Fix/route53 resolver rule remove defaults

[gaik180303]

Fix: Remove hardcoded defaults for port and protocol in aws_route53_resolver_rule target IP configuration

#41523

The aws_route53_resolver_rule resource previously hardcoded Default: 53 for port and Default: "Do53" for protocol in the target_ip block. This overrode the AWS API's conditional defaults. For example, the API automatically sets port to 443 when using DoH protocol and may auto-select DoH when the resolver endpoint only supports DoH. Because the provider always injected these defaults, it could lead to errors or incorrect behavior when the API expected different values.

Changes Made

internal/service/route53resolver/rule.go

• Removed explicit Default values for port and protocol in the target_ip schema.
• Replaced them with Optional: true and Computed: true so Terraform accepts values returned by the AWS API when users do not specify them.
• Updated expandRuleTargetIPs to only send port to the AWS API when it is explicitly provided (vPort != 0). This prevents sending a zero value and allows the API to apply its own default.
• Updated protocol handling so the field is only sent when explicitly set (vProtocol != ""), allowing the API to determine the correct protocol based on endpoint configuration.

internal/service/route53resolver/rule_test.go

• Updated TestAccRoute53ResolverRule_forwardMultiProtocol to explicitly set "Do53" in the first step since the provider no longer injects a default.
• Added TestAccRoute53ResolverRule_forwardAPIDefaults to verify that when port and protocol are omitted from configuration, the AWS API correctly assigns them. The test validates this using TestCheckResourceAttrSet.

Outcome

When port and protocol are omitted from the target_ip block, the AWS API now applies its own conditional defaults. This aligns the provider behavior with the AWS API, CLI, and SDKs and avoids incorrect overrides caused by hardcoded defaults.

[github-actions]

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[github-actions]

✅ Thank you for correcting the previously detected issues! The maintainers appreciate your efforts to make the review process as smooth as possible.