Making build times considerably faster.
On my machine, after running `cargo clean`, `cargo build -p swap`
takes 2min 19s.
The updated dependency also comes with a critical fix to the `Scalar`
type, which originally wrongly assumed that secp256k1 and ed25519
scalars had the same endianness. For this reason, we now have to
reverse the bytes of recovered scalars if we are to use them on a
different chain.
Finally, there is no need to append `RUST_MIN_STACK=100000000` to
avoid stack overflows in tests and when running the binary.
There is some sort of timing issue when spinning up the monero containers on
github CI. I do not know exactly what is the cause but we have a configurable
'additional sleep time' already available for `testcontainers` that can resolve
this issue.
Use the environment variable MONERO_ADDITIONAL_SLEEP_PERIOD to tell
`testcontainers` to wait an additional 60 while bringing up the monero
container.
