Backport of increasing unit tests timeout from 10m to 30m into release/1.15.x

[hc-github-team-consul-core]

Backport

This PR is auto-generated from #19423 to be assessed for backporting due to the inclusion of the label backport/1.15.

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The person who merged in the original PR is:
@jmurret
This person should manually cherry-pick the original PR into a new backport PR,
and close this one when the manual backport PR is merged in.

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The below text is copied from the body of the original PR.

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Description

CI is failing when a whole test run goes over the default of 10m. This happens mostly with the agent package when the tests are split. and this happens more in enterprise with self hosted runners.

This change is to make it 30m which matches the integration tests setting.

Testing & Reproduction steps

Links

PR Checklist

• updated test coverage
• external facing docs updated
• appropriate backport labels added
• not a security concern

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Overview of commits

• 26cb1f6

[hashicorp-cla]

All committers have signed the CLA.

[github-team-consul-core-pr-approver]

Auto approved Consul Bot automated PR