derive: use latest compiletest_rs crate

Version 2.2 was not compiling any more: https://github.com/laumann/compiletest-rs/issues/51

derive/Cargo.toml

@@ -14,7 +14,7 @@ quote = "0.1.3"
 syn = "0.7.0"
 
 [dev-dependencies]
-compiletest_rs = "0.2.2"
+compiletest_rs = "0.2.5"
 
 [dev-dependencies.num]
 path = ".."