Pin coverage to 4.5.4

[AlexandreYang]

What does this PR do?

Pin coverage to 4.5.4 due to nedbat/coveragepy#883

INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/pytest_cov/engine.py", line 197, in finish
INTERNALERROR>     self.cov.stop()
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/control.py", line 613, in save
INTERNALERROR>     data = self.get_data()
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/control.py", line 667, in get_data
INTERNALERROR>     if self._collector and self._collector.flush_data():
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/collector.py", line 427, in flush_data
INTERNALERROR>     self.covdata.add_arcs(self.mapped_file_dict(self.data))
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/sqldata.py", line 468, in add_arcs
INTERNALERROR>     self._choose_lines_or_arcs(arcs=True)
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/sqldata.py", line 496, in _choose_lines_or_arcs
INTERNALERROR>     ('has_arcs', str(int(arcs)))
INTERNALERROR>   File "/home/vsts/work/1/s/mesos_slave/.tox/py27-1.0/lib/python2.7/site-packages/coverage/sqldata.py", line 1027, in execute
INTERNALERROR>     raise CoverageException("Couldn't use data file {!r}: {}".format(self.filename, exc))
INTERNALERROR> CoverageException: Couldn't use data file '/home/vsts/work/1/s/mesos_slave/.coverage': UNIQUE constraint failed: meta.key

See also build https://dev.azure.com/datadoghq/integrations-core/_build/results?buildId=4975&view=logs&j=bf4c800e-7111-54ee-c44f-8c9036bd969b&t=94e038dc-db7b-5e5b-22dc-1873a5f6c03e&l=80

Motivation

Additional Notes

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• PR title must be written as a CHANGELOG entry (see why)
• Files changes must correspond to the primary purpose of the PR as described in the title (small unrelated changes should have their own PR)
• PR must have changelog/ and integration/ labels attached

[codecov]

Codecov Report

Merging #5224 into master will decrease coverage by 14.15%.
The diff coverage is n/a.

Impacted Files	Coverage Δ
windows_service/tests/common.py
disk/datadog_checks/disk/__init__.py
win32_event_log/tests/test_check.py
...service/datadog_checks/windows_service/__init__.py
..._checks_base/datadog_checks/base/checks/network.py
...adog_checks_base/datadog_checks/base/utils/date.py
...ent_log/datadog_checks/win32_event_log/__init__.py
..._checks_base/datadog_checks/base/utils/db/query.py
datadog_checks_base/tests/test_kube_leader.py
datadog_checks_base/tests/test_warnings_util.py
... and 181 more