"unlinkat ([path]) (Directory not empty)" errors with experimental_worker_for_repo_fetching

### Description of the bug:

After upgrading to Bazel 7.2.0 and removing `--experimental_worker_for_repo_fetching=off` from `.bazelrc` (because https://github.com/bazelbuild/bazel/issues/21803 was fixed), we started to observe failures of the following form:

```
ERROR: /home/circleci/figma/WORKSPACE.bazel:157:27: fetching node_repositories rule //external:nodejs_linux_amd64: java.io.IOException: unlinkat (/home/circleci/.cache/bazel/_bazel_circleci/a6e8cb0ce75ceb1ea1faa0cca0b0ae0d/external/nodejs_linux_amd64/bin/nodejs) (Directory not empty)
ERROR: no such package '@@nodejs_linux_amd64//': unlinkat (/home/circleci/.cache/bazel/_bazel_circleci/a6e8cb0ce75ceb1ea1faa0cca0b0ae0d/external/nodejs_linux_amd64/bin/nodejs) (Directory not empty)
```

These errors appear to be linked with repository fetch restarts, particularly "fetch interrupted due to memory pressure; restarting". In two of two cases where I have seen this error, it happened in a repo where the repo fetch got restarted, judging by either the presence of that log message or the JSON trace profile.

### Which category does this issue belong to?

_No response_

### What's the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.

_No response_

### Which operating system are you running Bazel on?

Linux

### What is the output of `bazel info release`?

release 7.2.0

### If `bazel info release` returns `development version` or `(@non-git)`, tell us how you built Bazel.

_No response_

### What's the output of `git remote get-url origin; git rev-parse HEAD` ?

_No response_

### If this is a regression, please try to identify the Bazel commit where the bug was introduced with bazelisk --bisect.

_No response_

### Have you found anything relevant by searching the web?

Bazel Slack discussion: https://bazelbuild.slack.com/archives/CA31HN1T3/p1718057176146129

### Any other information, logs, or outputs that you want to share?

_No response_