Update vendored crates flagged by RustSec to their newest semver-compatible
releases with `cargo update -p <crate>@<version>`:
  crossbeam-epoch 0.9.18 -> 0.9.21 (RUSTSEC-2026-0204)
  rustls 0.23.37 -> 0.23.45 (RUSTSEC-2026-0285)
  rustls-webpki 0.103.13 -> 0.103.15

--- a/Cargo.lock
+++ b/Cargo.lock
@@ -266,9 +266,9 @@
 
 [[package]]
 name = "crossbeam-epoch"
-version = "0.9.18"
+version = "0.9.21"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b82ac4a3c2ca9c3460964f020e1402edd5753411d7737aa39c3714ad1b5420e"
+checksum = "dc74980687109a3b14c72fd458107bf0baa1da1a1a805e178d15501ba9b86d9d"
 dependencies = [
  "crossbeam-utils",
 ]
@@ -1019,9 +1019,9 @@
 
 [[package]]
 name = "rustls"
-version = "0.23.37"
+version = "0.23.45"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "758025cb5fccfd3bc2fd74708fd4682be41d99e5dff73c377c0646c6012c73a4"
+checksum = "0d41d731c7d2f962d1ccc364cec258de3c0e93b38c2fb3ba97ac74513048d634"
 dependencies = [
  "log",
  "once_cell",
@@ -1043,9 +1043,9 @@
 
 [[package]]
 name = "rustls-webpki"
-version = "0.103.13"
+version = "0.103.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61c429a8649f110dddef65e2a5ad240f747e85f7758a6bccc7e5777bd33f756e"
+checksum = "f3c3cf1d8b1e7d4927e2d154c3fcb02979afb9939629c62cd9048d4f07b60ac2"
 dependencies = [
  "ring",
  "rustls-pki-types",