Use abs path for entrypoint and make it executable

[jprendes]

Recent versions of containerd-shim-wasmedge-v1 require that the wasm file be executable and resolvable using PATH.

[juntao]

Hello, I am a code review bot on flows.network. Here are my reviews of code commits in this PR.

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Commit b1ebb29a457ebedb64d10dca5033c9a7de81615d

Key changes:

• Used an absolute path ("/order_demo_service.wasm") for the entrypoint instead of just the file name ("order_demo_service.wasm").
• Made the "order_demo_service.wasm" file executable by adding the command "RUN chmod a+x order_demo_service.wasm".
• Added a line to copy the "order_demo_service.wasm" file from the build stage to the final image.

Potential problems:

• It is unclear if the path "/root/.wasmedge/bin/wasmedgec" is valid and accessible. If this path is incorrect or the binary is missing, the build process might fail.
• There might be a potential issue with the "RUN chmod a+x order_demo_service.wasm" command. It assumes that the "order_demo_service.wasm" file is located in the same directory where the Dockerfile is located. If the file is in a different directory, this command will fail and the image will not be built correctly.

[hydai]

Thanks for this.