[build] Update version to 3.7-SNAPSHOT

[lvyanquan]

Changes

This PR updates the version from 3.6-SNAPSHOT to 3.7-SNAPSHOT.

Modified files:

• pom.xml: Update <revision> from 3.6-SNAPSHOT to 3.7-SNAPSHOT
• Dockerfile: Update FLINK_CDC_VERSION from 3.6-SNAPSHOT to 3.7-SNAPSHOT
• docs/config.toml:
  • Update Version and VersionTitle from 3.6-SNAPSHOT to 3.7-SNAPSHOT
  • Add 3.6 to PreviousDocs list
• .github/workflows/build_docs.yml:
  • Update build branch matrix from release-3.4 to release-3.6
  • Update flink_alias from release-3.6 to release-3.7

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This PR is generated by QwenCoder.

[Copilot]

Pull request overview

Updates the project’s snapshot version to 3.7-SNAPSHOT across build, Docker packaging, documentation configuration, and the docs deployment workflow to keep published artifacts and docs aligned with the next development cycle.

Changes:

• Bump Maven ${revision} from 3.6-SNAPSHOT to 3.7-SNAPSHOT.
• Update Docker build argument FLINK_CDC_VERSION to 3.7-SNAPSHOT.
• Update docs version strings and add 3.6 to the previous docs list; adjust docs workflow branches/aliasing for 3.7.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
pom.xml	Updates Maven revision to 3.7-SNAPSHOT so all modules inherit the new snapshot version.
Dockerfile	Aligns Docker packaging version with the new snapshot build artifacts.
docs/config.toml	Updates displayed docs version and adds 3.6 to the “PreviousDocs” list.
.github/workflows/build_docs.yml	Updates docs build matrix to include release-3.6 and updates the alias mapping for the new snapshot cycle.

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[lvyanquan]

PTAL, @leonardBang.

[leonardBang]

+1 from my side