chore: Make sigstore an optional dep

process/Cargo.toml

@@ -25,7 +25,7 @@ os_pipe = { version = "1", features = ["io_safety"] }
 rand = "0.8"
 semver = { version = "1", features = ["serde"] }
 signal-hook = { version = "0.3", features = ["extended-siginfo"] }
-sigstore = { version = "0.9", features = ["full-rustls-tls", "cached-client", "sigstore-trust-root", "sign"], default-features = false }
+sigstore = { version = "0.9", features = ["full-rustls-tls", "cached-client", "sigstore-trust-root", "sign"], default-features = false, optional = true }
 tokio = { version = "1.39.2", features = ["rt", "rt-multi-thread"], optional = true }
 zeroize = { version = "1", features = ["aarch64", "derive", "serde"] }
 
@@ -51,7 +51,7 @@ blue-build-utils = { version = "=0.8.14", path = "../utils", features = ["test"]
 workspace = true
 
 [features]
-sigstore = ["dep:tokio"]
+sigstore = ["dep:tokio", "dep:sigstore"]
 
 [patch.crates-io]
 sigstore = { git = "https://github.com/gmpinder/sigstore-rs.git", rev = "3a804bff" }