feat: Updated the LoadSignerBinaryPath() function to support ~ and HOME variables to go back to the home directory

[angelahao6]

Updated the LoadSignerBinaryPath() function to support "~" and "HOME" variables

Previously, the LoadSignerBinaryPath() function did not support the shorthand for home directory for the "~" and "HOME" variables. I added logic to check for "~" and "HOME" and commented out the original LoadSignerBinaryPath() and plan on cleaning up that comment later after this has been approved when I no longer need to reference the original version of the function.

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-- conventional-commit-lint bot https://conventionalcommits.org/

[clundin25]

@angelahao6 thanks! Please sign the Google CLA