docs: fix AEP-42 internal reference

[tharune]

Summary

• Replace AEP-42's dead ovrclk/aeps link to AEP-34 with an internal AEP reference

Verification

• Confirmed https://github.com/ovrclk/aeps/tree/main/spec/aep-34 returns HTTP 404
• Confirmed the current website repository contains src/content/aeps/aep-34
• Confirmed the local AEP-34 target directory exists
• Ran git diff --check

[tharune]

Closing this here because the AEP content lives in the AEP repository. Recreated in the correct repo: akash-network/AEP#105