GA encrypted_interconnect_router on compute router

[modular-magician]

Fixes tests in GA provider that were passing in beta provider.

This field should hav been released in GA along with GoogleCloudPlatform/magic-modules#4983 and GoogleCloudPlatform/magic-modules#4777

TF_ACC=1 TF_SCHEMA_PANIC_ON_ERROR=1 go test ./google -v -run=TestAccComputeHaVpnGateway_computeHaVpnGatewayEncryptedInterconnectExample -timeout 240m -ldflags="-X=github.com/hashicorp/terraform-provider-google/version.ProviderVersion=acc"
=== RUN   TestAccComputeHaVpnGateway_computeHaVpnGatewayEncryptedInterconnectExample
=== PAUSE TestAccComputeHaVpnGateway_computeHaVpnGatewayEncryptedInterconnectExample
=== CONT  TestAccComputeHaVpnGateway_computeHaVpnGatewayEncryptedInterconnectExample
--- PASS: TestAccComputeHaVpnGateway_computeHaVpnGatewayEncryptedInterconnectExample (105.92s)
PASS

TF_ACC=1 TF_SCHEMA_PANIC_ON_ERROR=1 go test ./google -v -run=TestAccComputeInterconnectAttachment_computeInterconnectAttachmentIpsecEncryptionExample -timeout 240m -ldflags="-X=github.com/hashicorp/terraform-provider-google/version.ProviderVersion=acc"
=== RUN   TestAccComputeInterconnectAttachment_computeInterconnectAttachmentIpsecEncryptionExample
=== PAUSE TestAccComputeInterconnectAttachment_computeInterconnectAttachmentIpsecEncryptionExample
=== CONT  TestAccComputeInterconnectAttachment_computeInterconnectAttachmentIpsecEncryptionExample
--- PASS: TestAccComputeInterconnectAttachment_computeInterconnectAttachmentIpsecEncryptionExample (82.78s)
PASS

TF_ACC=1 TF_SCHEMA_PANIC_ON_ERROR=1 go test ./google -v -run=TestAccComputeRouter_computeRouterEncryptedInterconnectExample -timeout 240m -ldflags="-X=github.com/hashicorp/terraform-provider-google/version.ProviderVersion=acc"
=== RUN   TestAccComputeRouter_computeRouterEncryptedInterconnectExample
=== PAUSE TestAccComputeRouter_computeRouterEncryptedInterconnectExample
=== CONT  TestAccComputeRouter_computeRouterEncryptedInterconnectExample
--- PASS: TestAccComputeRouter_computeRouterEncryptedInterconnectExample (59.94s)
PASS

in the GA provider.

If this PR is for Terraform, I acknowledge that I have:

• Searched through the issue tracker for an open issue that this either resolves or contributes to, commented on it to claim it, and written "fixes {url}" or "part of {url}" in this PR description. If there were no relevant open issues, I opened one and commented that I would like to work on it (not necessary for very small changes).
• Generated Terraform, and ran make test and make lint to ensure it passes unit and linter tests.
• Ensured that all new fields I added that can be set by a user appear in at least one example (for generated resources) or third_party test (for handwritten resources or update tests).
• Ran relevant acceptance tests (If the acceptance tests do not yet pass or you are unable to run them, please let your reviewer know).
• Read the Release Notes Guide before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

compute: added `encrypted_interconnect_router` to `google_compute_router` (GA only)

Derived from GoogleCloudPlatform/magic-modules#5397