fix: Invalid volume size for sys-bitcoin

[seven-beep]

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What does this PR aims to accomplish

Simple fix over a Invalid size: 1TI while performing sudo qubectl state.apply sys-bitcoin.create

What does this PR change

Change the unit measure from Ti to Gi.

[ben-grande]

:) thanks, I did not have a 1Ti drive to test and thought it was because of that it was failing, but yeah, LVMs can expand more than necessary.