Create modal: All the elements in the modal are not keyboard accessible

Issue Summary

In the create new page modal, some of the elements are not accessible with keyboard-only.

Steps to Reproduce

1. Navigate to the Confluence homepage.
2. Navigate to the "Create" button inside the header section & activate it.

Screenshot

Screen recording

CONFSERVER-79827.mov

Actual Results

In the Create modal, some of the interactive elements such as "Help" and "Add or customize templates for the selected space" links are not keyboard accessible. While the other elements in the modal receive keyboard focus and could be activated, and the following mentioned elements are not accessible with the keyboard only. Hence the keyboard users would find it difficult to access the modal elements effectively.

Expected Results

All the interactive elements in the modal should be able to receive the keyboard and screen reader focus. 
Ensure to remove the tabindex="-1" from the interactive elements such as "Add or customize templates for the selected space" links.
Remove the tabindex="100" from the <ol> element containing the Templates lists.
Ensure the focus order should be as follows:

1. Help link
2. Select space dropdown menu
3. Template lists
4. Add or customize templates for the selected space
5. Create button
6. Close button

Workaround

Currently, there is no known workaround for this behavior. A workaround will be added here when available