adding map to pscConnections.error.details field to ServiceConnectionPolicy

[felipegc]

Fixes: hashicorp/terraform-provider-google#15701

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).
• 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).
• Generated Terraform providers, and ran make test and make lint in the generated providers to ensure it passes unit and linter tests.
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• Read Write release notes before writing my release note below.

Release Note Template for Downstream PRs (will be copied)

networkconnectivity: added `psc_connections.error.details` field to `google_network_connectivity_service_connection_policy` resource

[modular-magician]

Hello! I am a robot. It looks like you are a: Community Contributor Googler Core Contributor. Tests will require approval to run.

@NickElliot, a repository maintainer, has been assigned to review your changes. If you have not received review feedback within 2 business days, please leave a comment on this PR asking them to take a look.

You can help make sure that review is quick by doing a self-review and by running impacted tests locally.

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes:

Diff report

Your PR generated some diffs in downstreams - here they are.

Terraform GA: Diff ( 2 files changed, 18 insertions(+))
Terraform Beta: Diff ( 2 files changed, 18 insertions(+))

[modular-magician]

Tests analytics

Total tests: 3008
Passed tests 2712
Skipped tests: 296
Affected tests: 0

$\textcolor{green}{\textsf{All tests passed in REPLAYING mode.}}$
View the build log

[NickElliot]

LGTM