Write minValidatorCount to genesis.json

[jp-imx]

Description

Re-open from this: #1535 (comment)

Write the value from the genesis '--min-validator-count' flag to the genesis.json output

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Breaking changes

Please complete this section if any breaking changes have been made, otherwise delete it

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

Manual tests

I ran the following command and verified the file:

./polygon-edge genesis --block-gas-limit 10000000 --epoch-size 10 \                                     
--validators-path ./ --validators-prefix test-chain- \
--consensus polybft \
--reward-wallet ... \
--transactions-allow-list-admin ... \
--transactions-allow-list-enabled ... \
--block-gas-limit ... \
--block-time ... \
--min-validator-count 3 \
--max-validator-count 100

Documentation update

Please link the documentation update PR in this section if it's present, otherwise delete it

Additional comments

Please post additional comments in this section if you have them, otherwise delete it

[jp-imx]

@goran-ethernal I didn't have access to re-open 1535 so I re-created it here.

[jp-imx]

@goran-ethernal / @igorcrevar thank you for reviewing these changes. I would appreciate your help with the next steps.

The "Pull Request CI / Test / Polygon Edge (pull_request)" check failed, but it seems to me like it's unrelated to the changes here. Also, I don't have access to merging this PR when we deem it ready.