Update Rust crate bitflags to 1.3

Author: renovate[bot]

Cargo.toml

@@ -28,7 +28,7 @@ url = "2.2"
 percent-encoding = "2.1"
 once_cell = "1.8"
 regex = "1.5"
-bitflags = "1.2"
+bitflags = "1.3"
 itertools = "0.10"
 idna = "0.2"
 serde =  { version = "1.0", features = ["derive", "rc"] }