Fix deprecated Atlassian field name

[fsto]

Proposed changes

Remove usage name in favor for accountId for Atlassian backend. Fixes Issue 517 - essentially a KeyError when trying to access name.

Atlassian deprecation notice 1 October 2018:

By 29 April 2019, we will remove personal data from the API that is used to identify users, such as username and userKey, and instead use the Atlassian account ID (accountId). Additionally, will be restricting the visibility of other personal data, such as email, in conjunction with a user's profile privacy settings.

Further down in the same deprecation notice:

Field	Change	Nullable	Notes
name	REMOVED	N/A	Use accountId instead.

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[nijel]

Merged, thanks for your contribution!