Add csv list of partial release users

[dju90]

To use with bin/oneoff/add_progress_v2_closed_beta_users.rb

Generation method:

1. Downloaded list of all teacher users who had used the progress view within the last 30 days
2. Filtered to users where the detected language was English (feature is not yet fully translated)
3. Randomly sampled 6000 rows (~20% of progress users) - used Excel's RAND() function to assign a random number to each row in the list, then sorted by the random number column, then deleted all rows past the first 6K

Geographic distribution of partial release is as follows:

• United States: 84.33%
• Canada: 7.47%
• United Kingdom: 3.60%
• Australia: 2.65%
• Pakistan: 0.52%
• Egypt: 0.43%
• Philippines: 0.35%
• Spain: 0.19%
• Qatar: 0.13%
• Puerto Rico: 0.13%
• Portugal: 0.11%
• Brazil: 0.09%