Update doctrine/coding-standard requirement from ^6.0 to ^6.0 || ^9.0

[dependabot-preview[bot]]

Updates the requirements on doctrine/coding-standard to permit the latest version.

Release notes

Sourced from doctrine/coding-standard's releases.

9.0.0

Release Notes for 9.0.0

9.0.0

• Total issues resolved: 0

• Total pull requests resolved: 1

• Total contributors: 1

• 238: Add psalm-prefixed annotations to param and return group thanks to @simonberger

• 241: Slevomat CS 7.0.0 and PHPCS 3.6.0 thanks to @kukulich

Commits

• 35a2452 Merge pull request #241 from kukulich/master
• 8d75920 Slevomat CS 7.0.0 and PHPCS 3.6.0
• 49386d9 Add psalm and phpstan prefixed annotations to param and return group
• 8294297 Merge remote-tracking branch 'origin/8.2.x' into 8.3.x
• 950c50a Revert "Add psalm and phpstan prefixed annotations to param and return group"
• 378aa39 Merge pull request #238 from simonberger/patch-1
• 7dfeaa9 Add psalm and phpstan prefixed annotations to param and return group
• fb2caa8 Merge pull request #237 from morozov/removed-unused-private
• d9ff91a Remove SlevomatCodingStandard.Classes.UnusedPrivateElements
• e6509e2 Merge pull request #223 from doctrine/dependabot/composer/slevomat/coding-sta...
• 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:

• 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)