Update crossbeam-utils requirement from 0.7 to 0.8

[dependabot-preview[bot]]

Updates the requirements on crossbeam-utils to permit the latest version.

Changelog

Sourced from crossbeam-utils's changelog.

Version 0.8.0

• Bump the minimum supported Rust version to 1.36.
• Bump crossbeam-channel to 0.5.
• Bump crossbeam-deque to 0.8.
• Bump crossbeam-epoch to 0.9.
• Bump crossbeam-queue to 0.3.
• Bump crossbeam-utils to 0.8.

Version 0.7.3

• Fix breakage with nightly feature due to rust-lang/rust#65214.
• Bump crossbeam-channel to 0.4.
• Bump crossbeam-epoch to 0.8.
• Bump crossbeam-queue to 0.2.
• Bump crossbeam-utils to 0.7.

Version 0.7.2

• Bump crossbeam-channel to 0.3.9.
• Bump crossbeam-epoch to 0.7.2.
• Bump crossbeam-utils to 0.6.6.

Version 0.7.1

• Bump crossbeam-utils to 0.6.5.

Version 0.7.0

• Remove ArcCell, MsQueue, and TreiberStack.
• Change the interface of ShardedLock to match RwLock.
• Add SegQueue::len().
• Rename SegQueue::try_pop() to SegQueue::pop().
• Change the return type of SegQueue::pop() to Result.
• Introduce ArrayQueue.
• Update dependencies.

Version 0.6.0

• Update dependencies.

Version 0.5.0

• Update crossbeam-channel to 0.3.
• Update crossbeam-utils to 0.6.
• Add AtomicCell, SharedLock, and WaitGroup.

Version 0.4.1

• Fix a double-free bug in MsQueue and SegQueue.

Commits

• d9dfc9e Merge #581
• 2a3d84b Prepare for the next release
• 5ea6e70 Merge #580
• b363b3d Fix UB in destroy_array test
• e08b21c Merge #577
• 6217abf Ignore clippy::match_like_matches_macro lint
• 9cbfae7 Update cfg-if to 1
• 2444749 Merge #574
• 619f7db Fixed a few typos
• 7cc8377 Better plot.py with Python 3 & remove hard code (#569)
• Additional commits viewable in compare view

Dependabot will resolve any conflicts with this PR as long as you don't alter it yourself. You can also trigger a rebase manually by commenting @dependabot rebase.

---

Dependabot commands and options

You can trigger Dependabot actions by commenting on this PR: - `@dependabot rebase` will rebase this PR - `@dependabot recreate` will recreate this PR, overwriting any edits that have been made to it - `@dependabot merge` will merge this PR after your CI passes on it - `@dependabot squash and merge` will squash and merge this PR after your CI passes on it - `@dependabot cancel merge` will cancel a previously requested merge and block automerging - `@dependabot reopen` will reopen this PR if it is closed - `@dependabot close` will close this PR and stop Dependabot recreating it. You can achieve the same result by closing it manually - `@dependabot ignore this major version` will close this PR and stop Dependabot creating any more for this major version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this minor version` will close this PR and stop Dependabot creating any more for this minor version (unless you reopen the PR or upgrade to it yourself) - `@dependabot ignore this dependency` will close this PR and stop Dependabot creating any more for this dependency (unless you reopen the PR or upgrade to it yourself) - `@dependabot use these labels` will set the current labels as the default for future PRs for this repo and language - `@dependabot use these reviewers` will set the current reviewers as the default for future PRs for this repo and language - `@dependabot use these assignees` will set the current assignees as the default for future PRs for this repo and language - `@dependabot use this milestone` will set the current milestone as the default for future PRs for this repo and language - `@dependabot badge me` will comment on this PR with code to add a "Dependabot enabled" badge to your readme Additionally, you can set the following in your Dependabot [dashboard](https://app.dependabot.com): - Update frequency (including time of day and day of week) - Pull request limits (per update run and/or open at any time) - Out-of-range updates (receive only lockfile updates, if desired) - Security updates (receive only security updates, if desired)

[dependabot-preview[bot]]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.