Increase prometheus timeout

[mborsz]

What type of PR is this?

/kind bug

What this PR does / why we need it:

We are seeing that in some cases, the stateful pod (like prometheus) can be rescheduled and it can take even ~7m to start again due to volume remounting/6m force disk detach timeout.

Let's increase timeout to avoid failing test when this happens.

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[mborsz]

/assign @azylinski

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/assign @azylinski

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[mborsz]

/assign @marseel

[marseel]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: marseel, mborsz

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