Temporarily disable 0.5 since it's not collecting network_events

[hellais]

While we work towards releasing a probe-engine release that addresses: ooni/probe#2674, we should disable 0.5 for all users.

[hellais]

I have validated this works as intended on backend-hel, so I am going to proceed with merging it and deploying into prod.

This is the python script I used to validate it's working:

import requests
SHOULD_HAVE_FLAG_IP = '1.34.1.1'
SHOULD_NOT_HAVE_FLAG_IP = '1.1.1.1'

def get_check_in_features(ip, backend_addr):
    req_json = {
        'probe_cc': 'IT',
        'probe_asn': 'AS8220',
        'platform': 'desktop',
        'software_name': 'notooniprobe',
        'software_version': '1.0.0',
        'on_wifi': False,
        'charging': False,
        'run_type': 'manual',
        'web_connectivity': {
            'category_codes': []
        }
    }
    
    r = requests.post(
        backend_addr, 
        headers={
            "X-Forwarded-For": ip
        }, 
        json=req_json
    )
    j = r.json()
    return j['conf']['features']

# Currently deployed instance behaves differently depending on the octet
assert get_check_in_features(
    SHOULD_NOT_HAVE_FLAG_IP, "https://backend-fsn.ooni.org/api/v1/check-in"
).get('webconnectivity_0.5', False) == False

assert get_check_in_features(
    SHOULD_HAVE_FLAG_IP, "https://backend-fsn.ooni.org/api/v1/check-in"
).get('webconnectivity_0.5', False) == True

# With the fix they should both be set to false
assert get_check_in_features(
    SHOULD_NOT_HAVE_FLAG_IP, "https://backend-hel.ooni.org/api/v1/check-in"
).get('webconnectivity_0.5', False) == False

assert get_check_in_features(
    SHOULD_HAVE_FLAG_IP, "https://backend-hel.ooni.org/api/v1/check-in"
).get('webconnectivity_0.5', False) == False