Add trial suffix to can_extend and can_reactivate methods in the Namespace class

What does this MR do?

There are two methods in the Namespace class that we use for checking if the trial can be extended or reactivated. They are named as can_extend? and can_reactivate?. Seeing these methods in the code base might be misleading due to their names:

if namespace.can_extened?
# or 
if namespace.can_reactivate?

Let's add suffix trial to both of them to resolve that:

if namespace.can_extend_trial?
# or 
if namespace.can_reactivate_trial?

Closes #335965 (closed)

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