Make carbon-registry buildable in Java 11

[jsdjayanga]

Purpose

Make carbon-registry buildable in Java 11

Goals

Make carbon-registry buildable in Java 11

Approach

Make carbon-registry buildable in Java 11

User stories

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Release note

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Documentation

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Training

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Certification

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Marketing

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Automation tests

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Security checks

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Samples

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Related PRs

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Migrations (if applicable)

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Test environment

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Learning

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