pip: bump lmdb from 1.6.2 to 2.2.1

Bumps [lmdb](https://github.com/jnwatson/py-lmdb) from 1.6.2 to 2.2.1.
- [Changelog](https://github.com/jnwatson/py-lmdb/blob/master/ChangeLog)
- [Commits](jnwatson/py-lmdb@py-lmdb_1.6.2...py-lmdb_2.2.1)

---
updated-dependencies:
- dependency-name: lmdb
  dependency-version: 2.2.1
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

tests/requirements.txt

@@ -9,7 +9,7 @@ torchtnt==0.2.4
 numba==0.65.1
 numpy==2.4.6
 scikit-learn==1.9.0
-lmdb==1.6.2
+lmdb==2.2.1
 pymatgen==v2026.5.4
 ray[serve]==2.56.0
 # Ray Serve 2.55.1 declares `protobuf>=3.20.3` with no upper bound, but is