Upgrade ActionCable npm package

What does this MR do?

We upgraded Rails in !31307 (merged). No actual update to ActionCable was included in this patch release but a package with the same version is always released.

We just upgrade this to match our current Rails version.

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

changed the description

changed milestone to %13.0

added backstage [DEPRECATED] devopsplan groupproject management labels

added maintenancedependency label

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Category	Reviewer	Maintainer
frontend	Jose Ivan Vargas (@jivanvl)	Martin Wortschack (@wortschi)

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mentioned in issue #210501 (closed)

@wortschi can you review please?

This is just an update for the versions to match. No actual code changes are in the version bump.

https://github.com/rails/rails/releases/tag/v6.0.3

assigned to @wortschi

approved this merge request

enabled an automatic merge when the pipeline for a387164a succeeds

@engwan Thank you, I've enabled MWPS on this.

merged

mentioned in commit 6b546d06

added workflowstaging label

added workflowcanary label and removed workflowstaging label

added workflowproduction label and removed workflowcanary label