7f8103dd762572f8b0f01514d0c32723d27c61e9 Fix typos in comments (thunderbiscuit)
Pull request description:
### Description
This PR fixes a bunch of small typos in comments. I'm getting acquainted with the codebase and found a few typos just by chance, and ended up going through it with an IDE searching for typos in all files.
### Notes to the reviewers
To be clear, this PR _only addresses typos that are within comments_.
### Checklists
* [x] I've signed all my commits
* [x] I followed the [contribution guidelines](https://github.com/bitcoindevkit/bdk/blob/master/CONTRIBUTING.md)
* [x] I ran `cargo fmt` and `cargo clippy` before committing
ACKs for top commit:
notmandatory:
ACK 7f8103dd762572f8b0f01514d0c32723d27c61e9
Tree-SHA512: eb3f8f21cbd05de06292affd9ef69c21b52022dfdf25c562c8f4d9c9c011f18175dff0c650cb7efcfb2b665f2af80d9a153be3d12327c47796b0d00bfd5d9803
aa13186fb0