Remove incomplete imports

I tried importing chat history from Slack but failed to upload a couple of times. Now my “mmctl import list incomplete” still retains all these failed attempts. How do I remove them?

Here is what they look like:

$ mmctl import list incomplete
ID: 3tttsiop1pf67dcy8b5g3yze1w
Name: mattermost-bulk-import.zip  
Uploaded: 0/2821830428 (0%)
ID: ds9qcappjjgt9e3oa8w1sffkdo                                                                                                  Name: mattermost-bulk-import.zip
Uploaded: 0/2821830428 (0%)
ID: yhqjtukm7innukqa4jjrfiwtmy                                                                                                  Name: mattermost-bulk-import.zip
Uploaded: 2147479552/2821830428 (76%)
ID: cb5mkjmpkjgriru1hwdbhytxxc
Name: mattermost-bulk-import.zip
Uploaded: 2147479552/2821830428 (76%) 
ID: nbii8aoa5iyeifo135wcqbzs1c
Name: mattermost-bulk-import.zip
Uploaded: 0/2821830428 (0%)
ID: 3mk3dwy8gbnippygs9wegbm11e
Name: mattermost-bulk-import.zip
Uploaded: 2150100665/2821830428 (76%)
ID: p9pftz3uxbbmfkji1tydsie5sr
Name: mattermost-bulk-import.zip
Uploaded: 2150100665/2821830428 (76%)