Update re: adding SSH key to the ssh-agent for Mac users (Issue #23159) (#24505)

Co-authored-by: Anne-Marie <102995847+am-stead@users.noreply.github.com>

content/authentication/connecting-to-github-with-ssh/generating-a-new-ssh-key-and-adding-it-to-the-ssh-agent.md

@@ -155,7 +155,9 @@ Before adding a new SSH key to the ssh-agent to manage your keys, you should hav
 
    The `--apple-use-keychain` option is in Apple's standard version of `ssh-add`. In MacOS versions prior to Monterey (12.0), the `--apple-use-keychain` and `--apple-load-keychain` flags used the syntax `-K` and `-A`, respectively.
 
-   If you don't have Apple's standard version of `ssh-add` installed, you may receive an error. For more information, see "[Error: ssh-add: illegal option -- K](/articles/error-ssh-add-illegal-option-k)."
+  If you don't have Apple's standard version of `ssh-add` installed, you may receive an error. For more information, see "[Error: ssh-add: illegal option -- K](/articles/error-ssh-add-illegal-option-k)."
+  
+  If you continue to be prompted for your passphrase, you may need to add the command to your `~/.zshrc` file (or your `~/.bashrc` file for bash).
 
    {% endnote %}