Expiration time for exported objects should be configurable

[lmsurpre]

Is your feature request related to a problem? Please describe.
In #882 we added support for using presigned URLs for clients to fetch the resources.
Currently the expiration period for these is 24 hours (86400 seconds).

Besides this, we also support setting an ACL policy for objects (to make them temporarily public). I believe that is currently hard-coded to 2 hours.

Describe the solution you'd like
At least the presigned expiration period should be configurable.
I think the ACL one can stay at 2 hours because I want to mark that deprecated anyway (#2054).

Describe alternatives you've considered
Continue hard-coding it.

Acceptance Criteria
At least one acceptance criteria is included.

1. GIVEN a config with presigned=false and isPublic=true and an expiration time of 10 minutes
   WHEN an export is performed
   AND more than 10 minutes elapses
   THEN any existing download request should succeed
   AND the user should no longer be able to start new downloads from the provided URLs

2. GIVEN a config with presigned=true and isPublic=false and an expiration time of 10 minutes
   WHEN an export is performed
   AND more than 10 minutes elapses
   THEN any existing download request should succeed
   AND the user should no longer be able to start new downloads from the provided URLs

Additional context
As mentioned in the docs:

Please note that IBM COS does not support expiration time for each single COS object, so please configure retention policy (e.g, 1 day) for the bucket if IBM COS is used.

[prb112]

There are four spots that need to be updated to support this... DownloadUrl ConfigurationAdapter AbstractConfigurationAdapterImpl and the Users guide.

[lmsurpre]

I set presignedExpiry to 3600 (1 hour) in our connectathon environment and kicked off a big export.
After completion, I used the presigned urls from the $bulkdata-status operation to download the files.
At 59 minutes, I kicked off a bunch of donwloads.
While they were downloading, I kicked off some more after 60 minutes.
The ones I kicked off after 60 minutes failed as expected (ExpiredRequest) while the ones I kicked off at 59 minutes completed with success (even after the 60 minute mark).

I then invoked the $bulkdata-status endpoint again and confirmed that I received new links which worked for downloading the content.

This all worked very well and I'm quite happy :-)