Fix GCloud IT: test_max_messages error

[CamiRomero]

Related issue
Close #3033

Description

The test test_max_messages was a flaky test because sometimes the test takes the last log received with the amount 0. To solve this problem:

• We changed the callback function callback_received_messages_number, now returning all the matches.
• We need to refactor the test in order to use the new callback function
• We add a new assertion that checks that the module will only pull messages up to the limit

Modules Involved:

• tests/integration/test_gcloud/test_functionality/test_max_messages.py
• deps/wazuh_testing/wazuh_testing/gcloud.py

Logs example

Tests Results

Test Path	Os/Type	Execution Type	Results	Date	By
tests/integration/test_gcloud/test_functionality/test_max_messages.py	CentOS - Manager	Jenkins	🟢 🟢 🟢	27/06/2022	@CamiRomero

Tests

• Proven that tests pass when they have to pass.
• Proven that tests fail when they have to fail.

• Python codebase satisfies PEP-8 style style guide. pycodestyle --max-line-length=120 --show-source --show-pep8 file.py.
• Python codebase is documented following the Google Style for Python docstrings.

[damarisg]

Tests Results

Test Path	Os/Type	Execution Type	Results	Date	By
tests/integration/test_gcloud/test_functionality/test_max_messages.py	CentOS - Manager	Jenkins	🟢 🟢 🟢 🟢	16/06/2022	Seyla