Remove bson dev dependency

This dependency is conflicting with pymongo and resulting in the
following exception:

----
ImportError while importing test module '/var/lib/jenkins/workspace/cmk_master/unit_tests/check_mk/tests/unit/agents/plugins/test_mk_mongodb.py'.
Hint: make sure your test modules/packages have valid Python names.
Traceback:
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/_pytest/python.py:507: in _importtestmodule
    mod = self.fspath.pyimport(ensuresyspath=importmode)
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/py/_path/local.py:701: in pyimport
    __import__(modname)
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/_pytest/assertion/rewrite.py:304: in load_module
    exec(co, mod.__dict__)
unit/agents/plugins/test_mk_mongodb.py:5: in <module>
    from bson.json_util import loads
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/bson/json_util.py:116: in <module>
    from pymongo.errors import ConfigurationError
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/pymongo/__init__.py:77: in <module>
    from pymongo.collection import ReturnDocument
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/pymongo/collection.py:20: in <module>
    from bson.code import Code
../virtual-envs/2.7/.venv/local/lib/python2.7/site-packages/bson/code.py:18: in <module>
    from bson.py3compat import abc, string_type, PY3, text_type
E   ImportError: cannot import name abc
---

According to py-bson/bson#82 both
packages are conflicting and bson needs to be cleaned up.

Change-Id: I82383157176ba3230408285c142d7fc92cedccae

omd/packages/python-modules/python-modules.make

@@ -286,7 +286,6 @@ python-modules-dump-Pipfile:
 	@echo 'astroid = "*"  # used by testlib.pylint_checker_localization'
 	@echo 'bandit = "*"  # used by test/Makefile'"'"'s test-bandit target'
 	@echo '"beautifulsoup4" = "*"  # used by the GUI crawler and various tests'
-	@echo 'bson = "*"  # used by test_mk_mongodb unit test'
 	@echo 'compiledb = "*"  # used by the Livestatus/CMC Makefiles for building compile_command.json'
 	@echo 'docker = "*"  # used by test_docker test and mk_docker agent plugin'
 	@echo 'freezegun = "*"  # used by various unit tests'

virtual-envs/2.7/Pipfile

@@ -8,7 +8,6 @@ name = "pypi"
 astroid = "*"  # used by testlib.pylint_checker_localization
 bandit = "*"  # used by test/Makefile's test-bandit target
 "beautifulsoup4" = "*"  # used by the GUI crawler and various tests
-bson = "*"  # used by test_mk_mongodb unit test
 compiledb = "*"  # used by the Livestatus/CMC Makefiles for building compile_command.json
 docker = "*"  # used by test_docker test and mk_docker agent plugin
 freezegun = "*"  # used by various unit tests