remove procspawn dependency from crates which do not use it anyways (#848)

Cargo.lock

@@ -1941,7 +1941,6 @@ dependencies = [
  "memoffset",
  "mio",
  "paste",
- "procspawn",
  "rand 0.10.1",
  "rosenpass-cipher-traits",
  "rosenpass-ciphers",
@@ -2127,7 +2126,6 @@ dependencies = [
  "log",
  "mio",
  "postcard",
- "procspawn",
  "rand 0.10.1",
  "rosenpass-secret-memory",
  "rosenpass-to",

rosenpass/Cargo.toml

@@ -91,7 +91,6 @@ criterion = { workspace = true }
 test_bin = { workspace = true }
 stacker = { workspace = true }
 serial_test = { workspace = true }
-procspawn = { workspace = true }
 tempfile = { workspace = true }
 rustix = { workspace = true }
 serde_json = { workspace = true }

wireguard-broker/Cargo.toml

@@ -38,7 +38,6 @@ rosenpass-util = { workspace = true }
 
 [dev-dependencies]
 rand = { workspace = true }
-procspawn = { workspace = true }
 
 [features]
 experiment_api = ["rustix", "libc"]