mailmap: Add mailmap entry for Jeff Arnold.
mailmap: Add mailmap entry for Jeff Arnold.

andersk/zulip,andersk/zulip,hackerkid/zulip,zulip/zulip,hackerkid/zulip,andersk/zulip,hackerkid/zulip,brainwane/zulip,andersk/zulip,zulip/zulip,showell/zulip,kou/zulip,eeshangarg/zulip,zulip/zulip,zulip/zulip,kou/zulip,eeshangarg/zulip,kou/zulip,hackerkid/zulip,showell/zulip,punchagan/zulip,punchagan/zulip,hackerkid/zulip,andersk/zulip,brainwane/zulip,punchagan/zulip,rht/zulip,rht/zulip,punchagan/zulip,kou/zulip,showell/zulip,punchagan/zulip,andersk/zulip,zulip/zulip,showell/zulip,zulip/zulip,eeshangarg/zulip,brainwane/zulip,brainwane/zulip,showell/zulip,kou/zulip,punchagan/zulip,brainwane/zulip,hackerkid/zulip,rht/zulip,eeshangarg/zulip,zulip/zulip,hackerkid/zulip,rht/zulip,rht/zulip,kou/zulip,showell/zulip,eeshangarg/zulip,eeshangarg/zulip,rht/zulip,rht/zulip,punchagan/zulip,showell/zulip,brainwane/zulip,andersk/zulip,kou/zulip,brainwane/zulip,eeshangarg/zulip