Investigate alternative algorithms to RSA for webhook communication

[c-pius]

Description

Follow up from #1771

We want to investigate if there are alternative algorithms to RSA for our webhoook communication.

Reasons

RSA seems to be not state of the art any longer (see #1771 (comment)). In addition, we observed problems when testing RSA and 8192 bit key size: #1793

Acceptance Criteria

• investigated alternatives to RSA algorithm that are compliant with https://github.tools.sap/kyma/backlog/issues/5825
• understood and documented the tradeoffs when switching to a new algorithm (e.g., security, performance, ...)
• decided whether to stick with RSA or update to a new algorithm with the team and created necessary follow-ups
  • if changing to a new algorithm, Investigate support for 8192 self-signed-cert-key-size  #1793 can be closed

Timebox: 2 days (consider small PoC)

Feature Testing

No response

Testing approach

No response

Attachments

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