Don't specify proc-macro-test version

proc-macro-test is only used as a dev-dependency and isn't published to
crates.io, so a version doesn't make sense. Having a version also breaks
automatic publishing.

Author: davidlattimore

Cargo.toml

@@ -67,7 +67,6 @@ paths = { path = "./crates/paths", version = "0.0.0" }
 proc-macro-api = { path = "./crates/proc-macro-api", version = "0.0.0" }
 proc-macro-srv = { path = "./crates/proc-macro-srv", version = "0.0.0" }
 proc-macro-srv-cli = { path = "./crates/proc-macro-srv-cli", version = "0.0.0" }
-proc-macro-test = { path = "./crates/proc-macro-test", version = "0.0.0" }
 profile = { path = "./crates/profile", version = "0.0.0" }
 project-model = { path = "./crates/project-model", version = "0.0.0" }
 sourcegen = { path = "./crates/sourcegen", version = "0.0.0" }
@@ -80,6 +79,9 @@ tt = { path = "./crates/tt", version = "0.0.0" }
 vfs-notify = { path = "./crates/vfs-notify", version = "0.0.0" }
 vfs = { path = "./crates/vfs", version = "0.0.0" }
 
+# local crates that aren't published to crates.io. These should not have versions.
+proc-macro-test = { path = "./crates/proc-macro-test" }
+
 # In-tree crates that are published separately and follow semver. See lib/README.md
 line-index = { version = "0.1.0-pre.1" }
 la-arena = { version = "0.3.1" }