### Please describe the problem.


```
      retrieveKeyFile:                                  FAIL
          Exception: .git\annex\objects\fc0\296\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key: DeleteFile "\\\\?\\C:\\Users\\runneradmin\\.t\\main2\\.git\\annex\\objects\\fc0\\296\\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key\\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key": permission denied (Access is denied.)
        fsck downloaded object:                           OK (0.01s)
        retrieveKeyFile resume from 33%:                  FAIL
          Exception: .git\annex\tmp\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key: openBinaryFile: permission denied (Permission denied)
        fsck downloaded object:                           OK (0.01s)
        retrieveKeyFile resume from 0:                    FAIL
          Exception: .git\annex\tmp\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key: openFile: permission denied (Permission denied)
        fsck downloaded object:                           OK (0.01s)
cp: cannot create regular file '.git\annex\tmp\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key': Permission denied
        retrieveKeyFile resume from end:                  FAIL
          Exception: .git\annex\objects\fc0\296\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key: DeleteFile "\\\\?\\C:\\Users\\runneradmin\\.t\\main2\\.git\\annex\\objects\\fc0\\296\\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key\\SHA256E-s1048576--c347f274df214671e3bebb6674cc5d2e6c226d8358a416859d5fc3c79a08eb1f.this-is-a-test-key": permission denied (Access is denied.)
        fsck downloaded object:                           OK (0.01s)
        removeKey when present:                           OK (0.09s)
```

I think this fail is relatively recent since [5 days ago](https://github.com/datalad/git-annex/actions/runs/746941168) is green for git-annex (but red for datalad). Overall [today's log](https://github.com/datalad/git-annex/runs/2377452030?check_suite_focus=true) for 8.20210331-ge3de27dcc says `126 out of 833 tests failed (599.24s)` 

not sure if relates to [ubuntu build fails](https://git-annex.branchable.com/bugs/fresh_3_tests_fails-_openBinaryFile__58___resource_busy/)  which seems to be less wild, so filing separately

> Fixed by disabling the failing tests on windows, see comments for the
> gory details. [[done]] --[[Joey]] 
