Update box add action to pass arch correctly (#13699)

Currently, during the box add action env[:architecture] gets passed down to add_direct, however, there is no architecture in env, the correct arch which is set in Vagrantfile is box_architecture, this PR changes the action to pass down the correct parameter.

Closes: #13698, #13697

Author: taru-garg-hashicorp

lib/vagrant/action/builtin/box_add.rb

@@ -192,7 +192,7 @@ def add_direct(urls, env)
             env,
             checksum: env[:box_checksum],
             checksum_type: env[:box_checksum_type],
-            architecture: env[:architecture]
+            architecture: env[:box_architecture]
           )
         end
 

test/unit/vagrant/action/builtin/box_add_test.rb

@@ -114,11 +114,13 @@ def with_web_server(path, **opts)
 
       env[:box_name] = "foo"
       env[:box_url] = box_path.to_s
+      env[:box_architecture] = "x86_64"
 
       expect(box_collection).to receive(:add).with(any_args) { |path, name, version, opts|
         expect(checksum(path)).to eq(checksum(box_path))
         expect(name).to eq("foo")
         expect(version).to eq("0")
+        expect(opts[:architecture]).to eq("x86_64")
         expect(opts[:metadata_url]).to be_nil
         true
       }.and_return(box)