fix(platform): Fix timer & step-through block

[majdyz]

Background

Improvement on the Step Through Items & Timer block.

Changes 🏗️

• Avoid mixing data types for items input on Step Through Items block.
• Make input pins on CountDownTimer block non-advanced.
• Removed bold displayName on list input.
• Publish execution even on every yield, to allow block like StepThroughItem to produce output on every yield.

Testing 🔍

Note

Only for the new autogpt platform, currently in autogpt_platform/

• Create from scratch and execute an agent with at least 3 blocks
• Import an agent from file upload, and confirm it executes correctly
• Upload agent to marketplace
• Import an agent from marketplace and confirm it executes correctly
• Edit an agent from monitor, and confirm it executes correctly