Create liquibase YdbDatabase.java and CreateIndexGeneratorYdb.java

[KirillKurdyukov]

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Please check the type of change your PR introduces:

• [ ] Bugfix
• [x] Feature
• [ ] Code style update (formatting, renaming)
• [ ] Refactoring (no functional changes, no api changes)
• [ ] Build related changes
• [ ] Documentation content changes
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