Globally upgrade to syn 2.x and latest quote and proc_macro2 1x versions (#13846)

* globally upgrade quote to latest 1.0.x (1.0.26)

* globally upgrade syn to final 1.0.x version (1.0.109)

* globally upgrade proc-macro2 to 1.0.56

* upgrade to syn v2.0.13 and fix everything except NestedMeta

* fix parse nested metadata code in decl_runtime_apis.rs

* Port more stuff to syn 2.0

* Make the rest compile

* Ignore error

* update to syn 2.0.14

---------

Co-authored-by: Bastian Köcher <info@kchr.de>

substrate/frame/election-provider-support/solution-type/Cargo.toml

@@ -15,9 +15,9 @@ targets = ["x86_64-unknown-linux-gnu"]
 proc-macro = true
 
 [dependencies]
-syn = { version = "1.0.98", features = ["full", "visit"] }
-quote = "1.0"
-proc-macro2 = "1.0.37"
+syn = { version = "2.0.14", features = ["full", "visit"] }
+quote = "1.0.26"
+proc-macro2 = "1.0.56"
 proc-macro-crate = "1.1.3"
 
 [dev-dependencies]

substrate/frame/election-provider-support/solution-type/src/lib.rs

@@ -161,7 +161,7 @@ fn check_attributes(input: ParseStream) -> syn::Result<bool> {
 		return Ok(false)
 	}
 	let attr = attrs.pop().expect("attributes vec with len 1 can be popped.");
-	if attr.path.is_ident("compact") {
+	if attr.path().is_ident("compact") {
 		Ok(true)
 	} else {
 		Err(syn::Error::new_spanned(attr, "compact solution can accept only #[compact]"))
@@ -200,7 +200,7 @@ impl Parse for SolutionDef {
 						format!("Expected binding: `{} = ...`", expected),
 					))
 				},
-				syn::GenericArgument::Binding(syn::Binding { ident, ty, .. }) => {
+				syn::GenericArgument::AssocType(syn::AssocType { ident, ty, .. }) => {
 					// check that we have the right keyword for this position in the argument list
 					if ident == expected {
 						Ok(ty.clone())