Flaky fork snapshot test

[Michael-F-Bryan]

Describe the bug

The snapshot::test_snapshot_fork snapshot test depends on the ordering of print statements between a parent and child process, which can cause spurious failures, typically in CI.

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Snapshot Summary ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Snapshot file: tests/integration/cli/tests/snapshots/snapshot__snapshot_fork.snap
Snapshot: snapshot_fork
Source: tests/integration/cli/tests/snapshot.rs:714
────────────────────────────────────────────────────────────────────────────────
Expression: snapshot
────────────────────────────────────────────────────────────────────────────────
-old snapshot
+new results
────────────┬───────────────────────────────────────────────────────────────────
   14    14 │     "enable_network": false
   15    15 │   },
   16    16 │   "result": {
   17    17 │     "Success": {
   18       │-      "stdout": "Parent has x = 0\nParent memory is good\nChild has x = 2\nChild memory is good\nChild(2) exited with 3\n",
         18 │+      "stdout": "Parent has x = 0\nChild has x = 2\nParent memory is good\nChild memory is good\nChild(2) exited with 3\n",
   19    19 │       "stderr": "",
   20    20 │       "exit_code": 0
   21    21 │     }
   22    22 │   }
────────────┴───────────────────────────────────────────────────────────────────

You should be able to reproduce this error by running the following:

$ cargo build --package=wasmer-cli --features=cranelift,singlepass --release
$ while true; do
clear
cargo test --package wasmer-integration-tests-cli --test snapshot -- --exact test_snapshot_fork || break
done

Additional Information

This is similar to #3845, except instead of relying on the ordering of thread execution, we're relying on how the executor decides to schedule WASI processes.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

Feel free to reopen the issue if it has been closed by mistake.