Update deprecated code

[polsala]

• Usable with new server versions (6, 7, 8)
• Full py 3 compat
• Replace pymongo deprecated calls

Need: https://github.com/gisce/erp/pull/21911

Old coverage

Name                                                     Stmts   Miss  Cover
----------------------------------------------------------------------------
/home/psala/Projects/mongodb_backend/fields.py              53     53     0%
/home/psala/Projects/mongodb_backend/mongodb2.py           115     65    43%
/home/psala/Projects/mongodb_backend/orm_mongodb.py        366    228    38%
/home/psala/Projects/mongodb_backend/osv_mongodb.py         43     25    42%
----------------------------------------------------------------------------
TOTAL                                                      706    391    45%

New coverage

Name                                                     Stmts   Miss  Cover
----------------------------------------------------------------------------
/home/psala/Projects/mongodb_backend/fields.py              53      8    85%
/home/psala/Projects/mongodb_backend/mongodb2.py           115     65    43%
/home/psala/Projects/mongodb_backend/orm_mongodb.py        375    117    69%
/home/psala/Projects/mongodb_backend/osv_mongodb.py         43     25    42%
----------------------------------------------------------------------------
TOTAL                                                      855    235    73%

[github-actions]

Python Mongo 5 3.11 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.

[github-actions]

Python Mongo 3 2.7 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.

[github-actions]

Python Mongo 3 3.11 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.

[github-actions]

Python Mongo 5 2.7 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.

[github-actions]

Python Mongo 8 3.11 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.

[github-actions]

Python Mongo 8 2.7 Tests for mongodb_backend

84 tests   82 ✅  0s ⏱️
 2 suites   2 💤
 2 files     0 ❌

Results for commit 8d2a9cc.

♻️ This comment has been updated with latest results.