Doc: update basic community files for ASF

[tuhaihe]

fix #ISSUE_Number

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Change logs

In this commit, basic community files are udpated to follow the Apache rules and requests, including CoC, Security policy, and other places for a good project name.

Why are the changes needed?

Describe why the changes are necessary.

Does this PR introduce any user-facing change?

If yes, please clarify the previous behavior and the change this PR proposes.

How was this patch tested?

Please detail how the changes were tested, including manual tests and any relevant unit or integration tests.

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[yjhjstz]

LGTM

[edespino]

+1

My only followup is for us to consider adding the Apache Incubator Podling Powered by circle with Cloudberry logo.