Update environment variables for cng-trigger

What does this MR do and why?

Update environment variables for cng-trigger in accordance to latest changes introduced as part of: Merge changes from quality fork back to upstrea... (gitlab-org/quality/quality-engineering/team-tasks#3000 - closed)

Fixes currently periodically failing test-on-cng master pipelines.

Related to: Update CI setup for test-on-cng in gitlab project (gitlab-org/quality/quality-engineering/team-tasks#2996 - closed)

Closes: e2e-test-on-cng pipeline failed due to gitlab-r... (#492641 - closed)

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