fix(SC-1435): add validation for unsigned txHex matches client staking request

[henryyang183]

Description

Added more robust validation in light of recent npm module security breach

Issue Number

SC-1435

Type of change

Please delete options that are not relevant.

• Security improvement (non-breaking change which fixes an issue)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration.

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• My code compiles correctly for both Node and Browser environments
• I have commented my code, particularly in hard-to-understand areas
• My commits follow Conventional Commits and I have properly described any BREAKING CHANGES
• The ticket or github issue was included in the commit message as a reference
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes