Revert "ref(spin.toml): update with spinframework redirects"

[vdice]

Reverts #1497

Seeing the following in the app logs when navigating to /spin endpoints:

2025-04-10T21:42:40.317572Z ERROR spin_trigger_http: Error processing request: error while executing at wasm backtrace:
    0: 0x3d7b5 - <unknown>!<wasm function 298>
    1: 0x4e852 - wit-component:adapter:wasi_snapshot_preview1!allocate_stack
    2: 0x4b1ec - wit-component:adapter:wasi_snapshot_preview1!cabi_export_realloc

Caused by:
    wasm trap: wasm `unreachable` instruction executed    

Suspect it is the updated spin-redirect module and incompatibility with the older/pinned spin version we use for spin up-ing the website

[github-actions]

🚀 preview deployed successfully to Fermyon Cloud and available at https://fermyon-developer-pr-1523-ksm0y6us.fermyon.app