Update crate closure-ffi-proc-macros

Author: bors

cl/os/closure-ffi-proc-macros

@@ -9,3 +9,4 @@
 {"name":"closure-ffi-proc-macros","vers":"2.1.0","deps":[{"name":"proc-macro2","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"quote","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"syn","req":"^2.0","features":["full","visit","visit-mut"],"optional":false,"default_features":true,"target":null,"kind":"normal"}],"cksum":"e262eabccdc88e64d671e587f61835c027c8f5b538e258e5ae2aa09dd48b4167","features":{},"yanked":false}
 {"name":"closure-ffi-proc-macros","vers":"2.2.0","deps":[{"name":"proc-macro2","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"quote","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"syn","req":"^2.0","features":["full","visit","visit-mut"],"optional":false,"default_features":true,"target":null,"kind":"normal"}],"cksum":"ddc54f619e23cde0da050e7a28638d6981713b9d7536328415b20dc2b8561c61","features":{},"yanked":false}
 {"name":"closure-ffi-proc-macros","vers":"2.3.0","deps":[{"name":"proc-macro2","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"quote","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"syn","req":"^2.0","features":["full","visit","visit-mut"],"optional":false,"default_features":true,"target":null,"kind":"normal"}],"cksum":"c5cbe8e6ec2f2a04987dd84382036b8554a0fd135e748dc50275b406fb2a1c13","features":{},"yanked":false}
+{"name":"closure-ffi-proc-macros","vers":"2.4.0","deps":[{"name":"proc-macro2","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"quote","req":"^1.0","features":[],"optional":false,"default_features":true,"target":null,"kind":"normal"},{"name":"syn","req":"^2.0","features":["full","visit","visit-mut"],"optional":false,"default_features":true,"target":null,"kind":"normal"}],"cksum":"5ca0e9fe20ae037a940a3d5b82fc2273056908144dcdb3bb18b142256c7ba6bf","features":{},"yanked":false}