Update crate std-macro-extensions

Author: bors

st/d-/std-macro-extensions

@@ -34,3 +34,4 @@
 {"name":"std-macro-extensions","vers":"0.20.5","deps":[],"cksum":"62b1d584e03ca7e024b8abd29c1cfabb33722305cd504535a631edad79cf1f78","features":{},"yanked":false}
 {"name":"std-macro-extensions","vers":"0.21.0","deps":[],"cksum":"154a164a9901fa9fc9db90f614215320d0e3ea8a7cab79be94d3004878adcecb","features":{},"yanked":false}
 {"name":"std-macro-extensions","vers":"0.21.1","deps":[],"cksum":"723e95168fe3231183f108f3f3418afe93b182bab9d39b907594c013e5e9fa02","features":{},"yanked":false}
+{"name":"std-macro-extensions","vers":"0.21.2","deps":[],"cksum":"6491c9136ea643a818cd43ef4c66c7d4f82e6f83980f27cca72e03287ff2f509","features":{},"yanked":false}