docs: make v2 the current version

[tatomyr]

What/Why/How?

Make v2 the current version in the docs.

Reference

Release PR: #2219.

Testing

Screenshots (optional)

Check yourself

• Code changed? - Tested with Redoc/Realm/Reunite (internal)
• All new/updated code is covered by tests
• New package installed? - Tested in different environments (browser/node)

Security

• The security impact of the change has been considered
• Code follows company security practices and guidelines

[changeset-bot]

⚠️ No Changeset found

Latest commit: f021ec2

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

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[github-actions]

Command	Mean [s]	Min [s]	Max [s]	Relative
redocly lint packages/core/src/benchmark/benches/rebilly.yaml	1.387 ± 0.024	1.352	1.429	1.00
redocly-next lint packages/core/src/benchmark/benches/rebilly.yaml	1.410 ± 0.022	1.385	1.443	1.02 ± 0.02