Bump Zephyr to tip of main (3.4.0+)

[mniestroj]

Blocker: https://github.com/zephyrproject-rtos/zephyr/issues/59850

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[sam-golioth]

Can we close this PR in favor of #412?

[mniestroj]

Can we close this PR in favor of #412?

Sure, we can have a single PR. I left two separate PRs, just because I haven't tested fully the "second" bump.

[mniestroj]

Closing in favour of #412.