Links, typos, uniformity

[otkd]

• Adds links for each control to the OWASP Proactive Controls document (Follows same structure as Index Top10)
• Updates links on Index Top 10
• Changes Multi-factor to Multifactor as per cheat sheet name
• Typos

Thank you for submitting a Pull Request (PR) to the Cheat Sheet Series.

🚩 If your PR is related to grammar/typo mistakes, please double-check the file for other mistakes in order to fix all the issues in the current cheat sheet.

Please make sure that for your contribution:

• In case of a new Cheat Sheet, you have used the Cheat Sheet template.
• All the markdown files do not raise any validation policy violation, see the policy.
• All the markdown files follow these format rules.
• All your assets are stored in the assets folder.
• All the images used are in the PNG format.
• Any references to websites have been formatted as [TEXT](URL)
• You verified/tested the effectiveness of your contribution (e.g., the defensive code proposed is really an effective remediation? Please verify it works!).
• The CI build of your PR pass, see the build status here.

If your PR is related to an issue, please finish your PR text with the following line:

This PR covers issue #.

Thank you again for your contribution 😃