ASA Go: Update GWA cli for APS Gateway

**Describe the task**
A clear and concise description of what the task is.

**Acceptance Criteria**
- [ ] GWA cli is updated in CD pipeline

**Additional context**

You are receiving the following as a user of the API Services Portal. We plan to begin enforcing PKCE security for gwa-cli interactive user login. This change is NOT backwards compatible with current versions of the gwa-cli tool, so a new version (3.1.1) is now available for download that supports PKCE security.

More details on the changes can be found in the release notes
(https://developer.gov.bc.ca/docs/default/component/aps-infra-platform-docs/reference/releases/2026-may/).

When?
Date: Tuesday, May 12, 2026
Time: From 2:00 pm to 3:00 pm PDT
Will there be an impact on your existing services?
There will be no impact to your services currently configured in the API Services Portal.
What needs to be done?
Upgrade to gwa-cli version 3.1.1. This change applies only to interactive user login. Service account login is not impacted and continues to work with older versions of gwa-cli. Existing CI/CD tasks that use service accounts do not need to be updated for this change.
Users can safely upgrade to version 3.1.1 before the PKCE update on May 12, 2026.
Install the latest version of the gwa-cli using these instructions (https://developer.gov.bc.ca/docs/default/component/aps-infra-platform-docs/how-to/gwa-install/).

Locate the repository's CD pipeline configuration and identify where gwa-cli is installed or versioned. Check the current CLI version and update it to 3.1.1, then run the relevant pipeline validation. Done means the CD pipeline uses the newer version while service-account login remains supported.

Written by the indexing model from the issue text.