docs: removed duplicate `git_ssh_url` field from build event example
docs: removed duplicate `git_ssh_url` field from build event example

Previously the key `git_ssh_url` was listed twice in the example payload of an Build Event web hook.
stoplightio/gitlabhq,mmkassem/gitlabhq,dreampet/gitlab,axilleas/gitlabhq,jirutka/gitlabhq,stoplightio/gitlabhq,jirutka/gitlabhq,axilleas/gitlabhq,dreampet/gitlab,axilleas/gitlabhq,jirutka/gitlabhq,iiet/iiet-git,jirutka/gitlabhq,iiet/iiet-git,iiet/iiet-git,stoplightio/gitlabhq,iiet/iiet-git,dreampet/gitlab,stoplightio/gitlabhq,dreampet/gitlab,mmkassem/gitlabhq,axilleas/gitlabhq,mmkassem/gitlabhq,mmkassem/gitlabhq