Update base64 dependency from 0.20 to 0.22

Since base64 is re-exported, this is an API-breaking change.

Author: musicinmybrain

Cargo.toml

@@ -17,7 +17,7 @@ authors = [
 [dependencies]
 async-trait = "0.1.59"
 rand = "0.8.5"
-base64 = "0.20.0"
+base64 = "0.22.0"
 sha2 = "0.10.6"
 hmac = "0.12.1"
 serde_json = "1.0.89"