Bug 1556597 - Fix workspace warnings. r=Gankro

These warnings have been around forever; unused things in the workspace
Cargo.toml file that just need removing.

Differential Revision: https://phabricator.services.mozilla.com/D33781

--HG--
extra : moz-landing-system : lando

gfx/wr/Cargo.toml

@@ -1,5 +1,4 @@
 [workspace]
-license = "MPL-2.0"
 members = [
     "direct-composition",
     "examples",
@@ -16,4 +15,4 @@ panic = "abort"
 panic = "abort"
 
 [patch.crates-io]
-serde_derive = { git = "https://github.com/servo/serde", branch = "deserialize_from_enums10", feature="deserialize_in_place" }
+serde_derive = { git = "https://github.com/servo/serde", branch = "deserialize_from_enums10" }