update syn to 2 in web codegen (#3081)

actix-multipart-derive/CHANGES.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- Update `syn` dependency to `2`.
 - Minimum supported Rust version (MSRV) is now 1.65 due to transitive `time` dependency.
 
 ## 0.6.0 - 2023-02-26

actix-multipart-derive/Cargo.toml

@@ -17,11 +17,11 @@ all-features = true
 proc-macro = true
 
 [dependencies]
-darling = "0.14"
+darling = "0.20"
 parse-size = "1"
 proc-macro2 = "1"
 quote = "1"
-syn = "1"
+syn = "2"
 
 [dev-dependencies]
 actix-multipart = "0.6"