MigTD-Release-v0.4.0

Release content:
• Support cross platform migration SPR <-> EMR
• Add docker file to support reproducible build
• Bump some crates to close the security alert
• Devices/virtio-serial: fix incorrect return length
• deps: upgrade td-shim to a4a2488
• Upgrade rustls to v/0.22.0

Known issues:
• No known issue

For detailed changes please refer to https://github.com/intel/MigTD/issues?q=is%3Aissue+is%3Aclosed