once_cell only used with reqwest in download crate, so gate it

Author: klensy

download/Cargo.toml

@@ -10,14 +10,14 @@ default = ["reqwest-backend", "reqwest-rustls-tls", "reqwest-default-tls"]
 
 curl-backend = ["curl"]
 reqwest-backend = ["reqwest", "env_proxy"]
-reqwest-default-tls = ["reqwest/default-tls"]
-reqwest-rustls-tls = ["reqwest/rustls-tls-native-roots"]
+reqwest-default-tls = ["reqwest/default-tls", "dep:once_cell"]
+reqwest-rustls-tls = ["reqwest/rustls-tls-native-roots", "dep:once_cell"]
 
 [dependencies]
 anyhow.workspace = true
 curl = { version = "0.4.44", optional = true }
 env_proxy = { version = "0.4.1", optional = true }
-once_cell.workspace = true
+once_cell = { workspace = true, optional = true }
 reqwest = { version = "0.12", default-features = false, features = ["blocking", "gzip", "socks"], optional = true }
 thiserror.workspace = true
 url.workspace = true