GHSA-r275-fr43-pm7q: simple-git has blockUnsafeOperationsPlugin bypass via case-insensitive protocol.allow config key enables RCE

The `blockUnsafeOperationsPlugin` in simple-git fails to block unsafe git protocol overrides when the configuration key is written in uppercase or mixed case (like `PROTOCOL.ALLOW` instead of `protocol.allow`), because the security check uses a case-sensitive regex while git itself treats config keys case-insensitively. An attacker who controls arguments passed to git operations can exploit this to enable the `ext::` protocol, which allows arbitrary OS command execution (RCE, remote code execution where an attacker runs commands on a system they don't control).