NebulaGraph Operator v1.8.2

What's Changed

• [operator] Add pdb by @kevinliu24 in #521
• Coredump management by @kevinliu24 in #524
• fix(operator): remove unnecessary pod from autofailover list by @kevinliu24 in #530
• [operator] run leader balance multiple times until balanced. by @kevinliu24 in #532
• [operator] Add documentation for coredump preservation and pdb by @kevinliu24 in #533

Full Changelog: v1.8.1...v1.8.2