Proposal to adjust blocks per year param

This proposal is to correct the blocks per year parameter to be in line with the current network performance.

The original blocks per year parameter of 6311520 was calculated with the block time assumption of 5s. In reality, this block time has tracked closer to 6.247111s, which corresponds to 5048093 blocks per year.

Changing this parameter will result in the minting module changing to phase 2 closer to the anticipated time of 12 months after launch. Changing this parameter will also result in the mint per block increasing from 4.113319 juno per block to 5.142792 juno per block.

Please see further discusstion at https://commonwealth.im/juno/discussion/3170-proposal-to-decrease-the-blocks-per-year-parameter