Bug description

In v2.5.198 the PR #1978 got merged.
This PR added the new file DynamicAssemblyFactory.cs without a matching DynamicAssemblyFactory.cs.meta file.

This causes Unity to complain and not load MessagePack from versions v2.5.198 to the v2.5.302 (latests v2).

Repro steps

• Use a Unity LTS version
• Add MessagePack to PackageManager as Git reference by URL: https://github.com/MessagePack-CSharp/MessagePack-CSharp.git?path=src/MessagePack.UnityClient/Assets/Scripts/MessagePack#v2.5.302
• Watch Unity complain about DynamicAssemblyFactory.cs not having a .meta file and hence causing followup errors and eventually not loading the MessagePack package at all.

Expected behavior

There should be a DynamicAssemblyFactory.cs.meta file, such that Unity will properly load MessagePack added via Git URL.

Actual behavior

Unity complains:

The first 4 errors are follow-up errors due to the new DynamicAssemblyFactory.cs not being loaded.

Additional context

None.

It is just a missing .meta file. I would create the PR myself. But MessagePack has several branches and versions and I am simply not sure what the correct procedure is. I leave this to someone else with more experience.
I am willing to create the PR, if someone offers me basic instructions.