rev to 3.0.0-beta in preparation for publishing

[devoncarew]

• rev to 3.0.0-beta in preparation for publishing

I'd like to publish this as 3.0.0-beta (pre-release) in order to run the current lint set through a few code bases; that'll let us make sure the changes in analysis are ~what we'd expect.

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[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:lints	3.0.0-beta	ready to publish	v3.0.0-beta

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[pq]

I've made a late-breaking proposal for 3.0 in #154.

If you feel comfortable, I'm OK with landing this before we reach a decision on that. (I think we can still remove prefer_void_to_null for 3.0 even if there's a beta out that still has it.)

[devoncarew]

I've made a late-breaking proposal for 3.0 in #154.

If you feel comfortable, I'm OK with landing this before we reach a decision on that. (I think we can still remove prefer_void_to_null for 3.0 even if there's a beta out that still has it.)

Gotcha; this beta may not be the final word for 3.0.0; we still need to look into the analysis toggles around unintentional use of dynamic. We'll still have time to look at #154 and see if we think it should be in this release or no.

[devoncarew]

Looks like publishing automation here failed - Pubspec version (3.0.0-beta) and git tag (v3.0.0-beta) don't agree.. Perhaps due to incomplete handling of -beta versions? I'll manually publish from the tag and file an issue on firehose.

[devoncarew]

dart-lang/ecosystem#176