Bump dashmap to v5.3.4.

Author: adlerjohn

Cargo.toml

@@ -44,7 +44,7 @@ cfg-if = "1.0.0"
 async-h1 = { version = "2.0.0", optional = true }
 async-std = { version = "1.6.0", default-features = false, optional = true }
 async-native-tls = { version = "0.3.1", optional = true }
-dashmap = { version = "4.0.2", optional = true }
+dashmap = { version = "5.3.4", optional = true }
 deadpool = { version = "0.7.0", optional = true }
 futures = { version = "0.3.8", optional = true }