Fixes related to nightly and alloy

[LindaGuiga]

This PR introduces two fixes:

• Latest nightly made env::set_var unsafe, so this PR introduces an unsafe block when calling the method.
• It seems that the alloy library changed the second argument in get_block from a bool to a BlockTransactionKind (after updating rust, I got an error message complaining about the type of that argument), so this PR changes the const accordingly.

[Nashtare]

Note that the type change from alloy isn't due to nightly but to a bump in the deps. We should probably pin a specific commit for version control, so that we only upgrade at will, at least until the crates get published.

[atanmarko]

@Nashtare @LindaGuiga Regression tested with Jerigon, seems all good.

[atanmarko]

Note: #[allow(unused_unsafe)] was added in order not to break clippy before latest nightly(1.81.0-nightly). We will remove it when it becomes redundant.

[Nashtare]

Note that the PR has been merged without addressing this:

Note that the type change from alloy isn't due to nightly but to a bump in the deps. We should probably pin a specific commit for version control

which is what caused the build to break in the first place.

[atanmarko]

@Nashtare My bad. I'll open another ticket to fix alloy versions. I could do that after we test and merge #81 ?

[Nashtare]

Yeah sure.