fix: Resolve flaky address_controller test for web

apps/block_scout_web/test/block_scout_web/controllers/api/v2/address_controller_test.exs

@@ -159,6 +159,11 @@ defmodule BlockScoutWeb.API.V2.AddressControllerTest do
       tx_hash = to_string(tx.hash)
       address_hash = Address.checksum(proxy_address.hash)
 
+      {:ok, implementation_contract_address_hash} =
+        Chain.string_to_address_hash("0x" <> implementation_contract_address_hash_string)
+
+      checksummed_implementation_contract_address_hash = Address.checksum(implementation_contract_address_hash)
+
       insert(:proxy_implementation,
         proxy_address_hash: proxy_address.hash,
         proxy_type: "eip1167",
@@ -177,9 +182,9 @@ defmodule BlockScoutWeb.API.V2.AddressControllerTest do
                "watchlist_names" => [],
                "creator_address_hash" => ^from,
                "creation_tx_hash" => ^tx_hash,
-               "implementation_address" => "0x" <> ^implementation_contract_address_hash_string,
+               "implementation_address" => ^checksummed_implementation_contract_address_hash,
                "implementations" => [
-                 %{"address" => "0x" <> ^implementation_contract_address_hash_string, "name" => ^name}
+                 %{"address" => ^checksummed_implementation_contract_address_hash, "name" => ^name}
                ]
              } = json_response(request, 200)
     end