[master] Open file in binary mode when computing hash

[oogali]

What does this PR do?

What issues does this PR fix or reference?

Fixes #59014

Previous Behavior

SPM would open all files in text mode, causing an exception to be raised when traversing a file with binary or otherwise non-text content.

New Behavior

SPM opens all files in binary mode, resulting in no change for text files and avoiding exceptions on binary files.

Merge requirements satisfied?

[NOTICE] Bug fixes or features added to Salt require tests.

• Docs
• Changelog - https://docs.saltproject.io/en/master/topics/development/changelog.html
• Tests written/updated

Commits signed with GPG?

No

Please review Salt's Contributing Guide for best practices.

See GitHub's page on GPG signing for more information about signing commits with GPG.

[twangboy]

@oogali Could we get a changelog and a test written for this

[oogali]

@twangboy At the time I created this PR, I could not get the test suite to run per #66346.

[twangboy]

You should be able to pip install nox and then run the following:

nox -e "test-zeromq-3(coverage=False)" -- .\tests\pytests\unit\spm\test_pkgfiles.py --run-slow --core-tests --run-destructive