chore(deps) Update Rust crate base64 to 0.12.1 (#584)

tauri/Cargo.toml

@@ -16,7 +16,7 @@ webview-sys = "=0.5.0"
 web-view = "=0.6.2"
 tauri_includedir = "0.5.0"
 phf = "0.8.0"
-base64 = "0.12.0"
+base64 = "0.12.1"
 webbrowser = "0.5.2"
 lazy_static = "1.4.0"
 tiny_http = { version = "0.7", optional = true }