Khala Runtime Upgrade v1208 - motion #172

This motion will trigger the v1208 runtime upgrade for bug fixes:

• Storage performance fix for StakePool v2 upgrade
• Loosen condition check for confidence level 2 to reflect the Intel definition more accurately

For more details, please refer to: https://github.com/Phala-Network/khala-parachain/releases/tag/v0.1.20-khala-runtime-1208