CI: deploy-wasm workflow does not run when core files are updated

[ChinYikMing]

The Wasm deployment only runs when following files are updated:

files: |
              assets/html/index.html
              assets/js/pre.js
              build/*.elf

Updates to the core C files should also initiate deployment, as these changes could gain performance. Additionally, several prebuilt ELF executables are stored in the rv32emu-prebuilt directory, and the current method for detecting changes in ELF files is less effective. It should be revised to monitor updates in the rv32emu-prebuilt repository.