Update index.md

[debrutal]

Removing duplicate encryption algorithm

No Issue

Proposed changes

Deduplication of encryption algorith within the markdown

Checklist

• I have read the contributing guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security. vulnerability, I
  confirm that I got green light (please contact
  security@ory.sh) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

Further comments

Change just touches documentation for human being. No check of the above should be relevant AFAIK

[CLAassistant]

All committers have signed the CLA.

[aeneasr]

Awesome, thank you for your contribution!