fix: automount sa token not rendered and add tests to validate it

[davidgomesdev]

References

#75

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• The PR request is well described and justified, including the body and the references
• The PR title represents the desired changelog entry
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• Test coverage that demonstrates that the change works as expected
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Added a few tests to cover basic functionality (I admit it was written by AI, but I reviewed it before committing). Let me know if you want it removed for any reason.