[framework] adds copy to Sui::Url::Url (MystenLabs#2268)

crates/sui-framework/sources/Url.move

@@ -16,14 +16,14 @@ module Sui::Url {
     const EHashLengthMismatch: u64 = 0;
 
     /// Represents an arbitrary URL. Clients rendering values of this type should fetch the resource at `url` and render it using a to-be-defined Sui standard.
-    struct Url has store, drop {
+    struct Url has store, copy, drop {
         // TODO: validate URL format
         url: String,
     }
 
     /// Represents an arbitrary URL plus an immutable commitment to the underlying
     /// resource hash. Clients rendering values of this type should fetch the resource at `url`, and then compare it against `resource_hash` using a to-be-defined Sui standard, and (if the two match) render the value using the `Url` standard.
-    struct UrlCommitment has store, drop {
+    struct UrlCommitment has store, copy, drop {
         url: Url,
         resource_hash: vector<u8>,
     }