Thank you for your response. I eventually found an alternative solution at  https://bitbucket.org/blog/deprecating-atlassian-account-password-for-bitbucket-api-and-git-activity. Essentially, all I needed to do was to create an app password and enter it into the Xcode account for the Bitbucket repository. This seems to be the least disruptive solution, but I was unable to find it during my first search into the Bitbucket literature.