Bump lmdb from 1.6.2 to 1.7.2 in the requirements group (#3236)

Bumps the requirements group with 1 update: [lmdb](https://github.com/jnwatson/py-lmdb).


Updates `lmdb` from 1.6.2 to 1.7.2
- [Changelog](https://github.com/jnwatson/py-lmdb/blob/master/ChangeLog)
- [Commits](jnwatson/py-lmdb@py-lmdb_1.6.2...py-lmdb_1.7.2)

---
updated-dependencies:
- dependency-name: lmdb
  dependency-version: 1.7.2
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: requirements
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements_dev_optional.txt

@@ -1,6 +1,6 @@
 # optional library requirements
 # bsddb3==6.2.6; sys_platform != 'win32'
-lmdb==1.6.2; sys_platform != 'win32'
+lmdb==1.7.2; sys_platform != 'win32'
 # optional library requirements for Jupyter
 ipytree==0.2.2
 ipywidgets==8.1.7