fatal: ambiguous argument 'origin/master': unknown revision or path not in the working tree

See #319, release log:

• 9b921cb by @rultor: Merge branch '__rultor'
• 8201be5 by @yegor256: Merge pull request #322 from m...
• a3f1ef1 by @mbao01: [#321] update copyright date t...
• 627a519 by @mbao01: [#319] fetch all remotes befor...
• 8d8b8e1 by @rultor: Merge branch '__rultor'
• d448577 by @mbao01: [#308] fix rubocop issue

Released by Rultor 1.70.6, see build log