Add hello tests

[alinaliBQ]

Add command operator tests for hello, including the smoke test. Tests database hello behavior, output collection, syntax, and errors. Add the ReplicationTestCase class definition, also adds field build_expected(ctx, result=None). Adds Lte(Check) to property_checks.py that mirrors existing Gte(Check).

• Add compatibility test for hello #452

[documentdb-triage-tool]

🤖 Auto-triaged by documentdb-triage-tool.

Applied: compatibility test, enhancement
Project fields suggested: Component test-coverage · Priority P2 · Effort L · Status Needs Review
Confidence: 0.82 (mixed)

Reasoning

component from path globs (test-coverage, test-framework); effort from diff stats (1117+0 LOC, 14 files); LLM: Adds new test cases for the hello command (smoke, behavior, output, syntax, errors) plus supporting infrastructure like ReplicationTestCase, build_expected, and Lte(Check), spanning test-coverage and minor framework additions.

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