Problem: slashing fix not applied on mainnet

[yihuang]

Solution:

• add mainnet softfork height

👮🏻👮🏻👮🏻 !!!! REFERENCE THE PROBLEM YOUR ARE SOLVING IN THE PR TITLE AND DESCRIBE YOUR SOLUTION HERE !!!! DO NOT FORGET !!!! 👮🏻👮🏻👮🏻

PR Checklist:

• Have you read the CONTRIBUTING.md?
• Does your PR follow the C4 patch requirements?
• Have you rebased your work on top of the latest master?
• Have you checked your code compiles? (make)
• Have you included tests for any non-trivial functionality?
• Have you checked your code passes the unit tests? (make test)
• Have you checked your code formatting is correct? (go fmt)
• Have you checked your basic code style is fine? (golangci-lint run)
• If you added any dependencies, have you checked they do not contain any known vulnerabilities? (go list -json -m all | nancy sleuth)
• If your changes affect the client infrastructure, have you run the integration test?
• If your changes affect public APIs, does your PR follow the C4 evolution of public contracts?
• If your code changes public APIs, have you incremented the crate version numbers and documented your changes in the CHANGELOG.md?
• If you are contributing for the first time, please read the agreement in CONTRIBUTING.md now and add a comment to this pull request stating that your PR is in accordance with the Developer's Certificate of Origin.

Thank you for your code, it's appreciated! :)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 33.08%. Comparing base (1df9b2a) to head (3688204).

Additional details and impacted files

@@             Coverage Diff             @@
##           release/v4    #1040   +/-   ##
===========================================
  Coverage       33.08%   33.08%           
===========================================
  Files             127      127           
  Lines           20043    20043           
===========================================
  Hits             6631     6631           
  Misses          12351    12351           
  Partials         1061     1061           

Flag	Coverage Δ
integration_tests	20.71% <ø> (ø)
integration_tests_byzantine	9.66% <ø> (ø)
integration_tests_gov	10.02% <ø> (ø)
integration_tests_grpc	10.00% <ø> (ø)
integration_tests_ibc	24.80% <ø> (ø)
integration_tests_ledger	9.89% <ø> (ø)
integration_tests_slow	9.89% <ø> (ø)
integration_tests_solomachine	9.69% <ø> (ø)
integration_tests_upgrade	10.00% <ø> (ø)
unit_tests	10.99% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.