Limit persistence annotations to 63 chars

[nolar]

What do these changes do?

Limit Kopf's annotations' names to 63 characters.

Description

An issue found the hard way (though we hit it before): when an annotation's name is 64 or more characters, it is not accepted by K8s API. This is documented.

For example if we have a prefix, a long function name, and maybe a field suffix: kopf.zalando.org/some_resource_of_interest_created.status.childname — and oops, it is 67 already, while 63 is allowed.

This PR fixes the issue with lengthy handler ids by cutting their tail, and replacing it with some consistent one-way hash — this makes the annotation unique enough, and still recognisable/readable for the primary part of its name.

Issues/PRs

Issues: #331

Type of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist

• The code addresses only the mentioned problem, and this problem only
• I think the code is well written
• Unit tests for the changes exist
• Documentation reflects the changes
• If you provide code modification, please add yourself to CONTRIBUTORS.txt

[zincr]

🤖 zincr found 0 problems , 0 warnings

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[zincr]

🤖 zincr found 1 problem , 0 warnings

❌ Approvals
✅ Large Commits
✅ Specification
✅ Dependency Licensing

Details on how to resolve are provided below

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Approvals

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Not enough people have approved this pull request - please ensure that 1 additional user, who have not contributed to this pull request approve the changes.

• ✅ Approved by PR author @nolar
• ❌ 1 additional approval needed
   

[lgtm-com]

This pull request fixes 1 alert when merging 4761ec9 into 698171a - view on LGTM.com

fixed alerts:

• 1 for Unused import

[stehem]

👍