Matches Credential Manager Step to Installer

Installer 2.34.1 does not use "GIT Credential Manager Core" emphasized in these instructions and instead asks the user to choose between "Git Credential Manager" and "None".  This PR changes the step direction to match the option label in the installer.

Author: jimtuttle

_includes/install_instructions/shell.html

@@ -67,7 +67,7 @@ <h3>The Bash Shell</h3>
 		Ensure that "Default (fast-forward or merge) is selected and click "Next"
               </li>
               <li>
-		Ensure that "Git Credential Manager <strong>Core</strong>" is selected and click on "Next".
+		Ensure that "Git Credential Manager" is selected and click on "Next".
               </li>
               <li>
 		Ensure that "Enable file system caching" is selected and click on "Next".