The Test Team helps manage testing and triage across the WordPress ecosystem. They focus on user testing of the editing experience and WordPress dashboard, replicating and documenting bug reports, and supporting a culture of review and triage across the project.
As detailed in this Trac ticket, when you try to upload a new version of a pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party, you get an error. Meaning, if I have a plugin on my WordPress site that needs to be updated to the latest version, or even to a development version, I can’t just upload a new .zip file to do this. Instead I have to either update from the plugins page or upload a new folder via SFTPSFTP SFTP is an acronym for Secure File Transfer Protocol: A standard protocol to move computer files from one host to another over the Internet with enhanced security..
Following are the steps to replicate the existing issue where you get blocked when trying to upload a new version of a plugin: