* fix: no squeezing unfinalized proposals

Updates the PreimageOracle to correctly revert if a proposal has
not actually been finalized. This fixes a bug because the timestamp
is not set until after a proposal is finalized but all other
conditions in the squeeze function are met even before addLeaves
is called with the finalize boolean set.

* fix: ci checks

* fix: semver lock

---------
Co-authored-by: refcell <abigger87@gmail.com>