chore(deps): bump rustls-webpki to 0.103.10

[diegomrsantos]

Problem, Evidence, and Context (Required)

• cargo audit started failing on unstable because rustls-webpki 0.103.9 is flagged by RUSTSEC-2026-0049.
• This is worth doing now because it is breaking check-code in CI.
• Evidence: the failing advisory points to rustls-webpki 0.103.9 and recommends upgrading to >=0.103.10.
• Relevant links: https://rustsec.org/advisories/RUSTSEC-2026-0049

Change Overview (Required)

• Bump the lockfile entry for rustls-webpki from 0.103.9 to 0.103.10.
• Cargo also re-resolved data-encoding-macro-internal 0.1.17 to use syn 1.0.109 instead of syn 2.0.117. That crate declares syn >= 1, < 3, so this is a valid lockfile normalization rather than a behavior change.
• This is intentionally a minimal, lockfile-only fix. Start and end with Cargo.lock; there is no code change to review.
• Intentionally did not change any application code, dependency declarations, or unrelated audit warnings.

Risks, Trade-offs, and Mitigations (Required)

• Risk is low because this only updates a transitive dependency within the existing resolver bounds.
• The trade-off is that this does not address the pre-existing audit warnings for unmaintained/unsound crates; it only fixes the newly-failing vulnerability.
• Risk is mitigated by keeping the diff isolated to the lockfile and validating both cargo audit and a clean build afterwards.

Validation (Required)

• CARGO_HOME=/tmp/cargo-home-auditfix cargo audit
• CARGO_HOME=/tmp/cargo-home-auditfix cargo check -p eth --quiet

Rollback (Required for behavior or runtime changes; optional otherwise)

• Safe to revert by reverting this commit or downgrading the lockfile entry.
• No config, data, or operational changes.

Blockers / Dependencies (Optional)

• N/A

Additional Info / Next Steps (Optional)

• This was split out from the #904 work so the dependency fix can be reviewed and merged independently.