[code-reflection] RFR: Move liveness analysis to test

[Paul Sandoz]

Move liveness analysis to test. It is unused but is still a useful concept to explore test.

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Commit messages:
 - Move liveness analysis to test

Changes: https://git.openjdk.org/babylon/pull/835/files
  Webrev: https://webrevs.openjdk.org/?repo=babylon&pr=835&range=00
  Stats: 688 lines in 2 files changed: 324 ins; 358 del; 6 mod
  Patch: https://git.openjdk.org/babylon/pull/835.diff
  Fetch: git fetch https://git.openjdk.org/babylon.git pull/835/head:pull/835

PR: https://git.openjdk.org/babylon/pull/835