Change HTTP method to POST when using the API login endpoint

[mcarmona99]

This issue is part of wazuh/wazuh#12793.

The epic issue aims to change the API login endpoint method from GET to POST, as using GET as the method of a login endpoint is incorrect.

As it was said in wazuh/wazuh#10203 (comment), both GET /security/user/authenticate and POST /security/user/authenticate endpoints will coexist and the deprecation of GET /security/user/authenticate will happen in a future major release.

To avoid future problems when the actual login endpoint (GET) is deprecated, we should update all the references found in this repository:

• Occurrences of API_LOGIN_ENDPOINT

wazuh-qa/deps/wazuh_testing/wazuh_testing/api.py

Line 22 in 13db0b8

API_LOGIN_ENDPOINT = '/security/user/authenticate'

wazuh-qa/deps/wazuh_testing/wazuh_testing/api.py

Lines 53 to 65 in 13db0b8

	def get_token_login_api(protocol, host, port, user, password, login_endpoint, timeout, login_attempts, sleep_time):
	"""Get API login token"""
	login_url = f"{get_base_url(protocol, host, port)}{login_endpoint}"
	for _ in range(login_attempts):
	response = requests.get(login_url, headers=get_login_headers(user, password), verify=False, timeout=timeout)
	if response.status_code == 200:
	return json.loads(response.content.decode())['data']['token']
	time.sleep(sleep_time)
	else:
	raise RuntimeError(f"Error obtaining login token: {response.json()}")

wazuh-qa/deps/wazuh_testing/wazuh_testing/api.py

Line 70 in 13db0b8

login_token = get_token_login_api(protocol, host, port, user, password, login_endpoint, timeout, login_attempts,

wazuh-qa/tests/integration/test_api/test_config/test_request_timeout/test_request_timeout.py

Line 126 in 13db0b8

get_response = requests.get(f'{api.API_PROTOCOL}://{api.API_HOST}:{api.API_PORT}{api.API_LOGIN_ENDPOINT}',