Create alert for contributor user name and email modification

[Misjohns]

Contributor name and email MUST match GitHub account to avoid DCO failure

If a user alters the contributor Information section (user name and email), we need to warn them that these must match the name and email associated with their GitHub account for InstructLab to successfully submit their contribution. If these do not match, they will receive a DCO failure.

[Misjohns]

Knowledge contribution: Details > Contributor information

On the Details step, the UI auto-populates the contributor's name and email based on the GitHub account the user used during sign-in. If a user clicks on the pencil icon the Edit contributor information modal displays.

This modal will display information about the importance of their name and email matching their GitHub account for proper DCO sign-off. If user modifies the fields they will update on the Details step of the wizard.

Questions/concerns:

1. Some SMEs might not know what DCO signoff is or even how to verify what their GH name and email are.
2. Can/should a user modify their name/email per contribution?
3. If a user has more than a single GH account, do they have multiple iLab accounts?
4. Should this be handled at a higher level? A user's GH account populates their InstructLab profile and a user would need to modify any changes there?
5. How does a SME know their DCO has failed? Not indication in their dashboard currently. Do we need to support?
6. Need to advise the user that their GH email MUST be public. Can we resolve/enforce this during login?
   @vishnoianil @nerdalert