bump is-macro to 0.3 (RustPython#5066)

Author: jelmer

Cargo.lock

@@ -70,7 +70,7 @@ caseless = "0.2.1"
 getrandom = { version = "0.2.6", features = ["js"] }
 flamer = { version = "0.4", optional = true }
 half = "1.8.2"
-is-macro = "0.2.2"
+is-macro = "0.3"
 memchr = "2.4.1"
 memoffset = "0.6.5"
 optional = "0.5.0"