Removal of test mode flag in reposense code

[chan-j-d]

With PR #1911 that removes the only use of the test mode flag in reposense, I think we can consider removing it to avoid additional maintenance. The original test mode flag was introduced in this PR #1816 where it was necessary since it was not known that the system tests were not quite functioning properly.

The test mode flag is primarily used for implementing some test specific behavior in a reposense run which is currently not required. As such, I would like to put forward the suggestion that we remove related code and documentation for the test mode flag.

[sikai00]

I was initially hesitant on removing the test mode flag because the parallelization of system test in #1900 may require the flag. However given that the #1900 will not be merged, I believe it will be good to remove the test mode behavior. Currently I think it is only used to decide if the fresh cloning flag should be active or not. I believe it will be fine to have the fresh cloning flag as a standalone flag that does not require the test mode flag.

I think this would be a good first timer issue, as it mainly only involves removal of code related to test mode. What do you think?

[chan-j-d]

Sounds good to me @sikai00