remove pkg/proto/v0/accounts.mock.go

[butonic]

get rid of handwritten pkg/proto/v0/accounts.mock.go after owncloud/ocis-accounts#103 is merged and ocis-proxy is using the new mock.

[phil-davis]

@butonic this is an old issue that was transferred from the archived ocis-accounts repo a few weeks ago.
Please close if no longer relevant.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[refs]

@butonic I could bring the diff from https://github.com/owncloud/ocis-accounts/pull/103/files to accounts. Do we want this?

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 10 days if no further activity occurs. Thank you for your contributions.

[wkloucek]

accounts service was completely removed, therefore no longer valid