Fix: All toPb() methods access level changed to public

[TurtleBeatboxer]

Minor change, but requested in issue #1007

• Make sure to open an issue as a bug/issue before writing your code! That way we can discuss the change, evaluate designs, and agree on the general idea
• Ensure the tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

Fixes #1007 ☕️

[google-cla]

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[TurtleBeatboxer]

Why there are several non resolvable checks saying: "Expected - Waiting for the status to be reported" even though I did tests and reopened the pull request quite a few times?