test(s2n-quic-core): reduce const instruction counts

[camshaft]

Description of changes:

This fixes a few things after the most recent rust beta was released:

• There seems to have been a change in how const instructions were counted and resulted in the static stream data to fail (see const eval interpreter step limit being hit on nightly for long-running while loop rust-lang/rust#103814). I was able to get around this issue by replacing data.len() with DATA_LEN.
• The derive(Debug) for PhantomData now includes the inner T in its output. This breaks our snapshot tests so I've implemented a manual debug where it caused issues

Call-outs:

I also noticed that the s2n-quic crate had not updated its bolero dependency as part of #1552. I've also done that here.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.