## Bug description

When filtering insights by active feature flags, and trying to select a single feature flag (by using a `contains` selector), events are not being correctly filter (i.e. no events are returned). This presumably happens because the `active_feature_flags` attribute is stored as an array and the operator does not work properly on CH.

## Expected behavior

Relevant events should be loaded.

## How to reproduce

1. Create an insights graph, filter by "Active feature flags" using a contain selector.

Alternatively, just open [this graph](https://app.posthog.com/insights?actions=%5B%7B%22id%22%3A1578%2C%22name%22%3A%22created%20action%22%2C%22type%22%3A%22actions%22%2C%22order%22%3A0%7D%5D&events=%5B%5D&new_entity=%5B%5D&interval=week&date_from=-90d&breakdown=false&breakdown_type&properties=%5B%7B%22key%22%3A%22%24active_feature_flags%22%2C%22value%22%3A%22actions-ux-201012%22%2C%22operator%22%3A%22icontains%22%2C%22type%22%3A%22event%22%7D%5D).

## Environment

Cloud latest version.


#### *Thank you* for your bug report – we love squashing them!

CC @timgl 

ee/clickhouse/models/property.py
prop: Property, idx: int, prepend: str = "", prop_var: str = "properties"
) -> Tuple[str, Dict[str, Any]]:
    operator = prop.operator
    if operator == "is_not":
        params = {"k{}_{}".format(prepend, idx): prop.key, "v{}_{}".format(prepend, idx): prop.value}
        return (
            "AND NOT (trim(BOTH '\"' FROM JSONExtractRaw({prop_var}, %(k{prepend}_{idx})s)) = %(v{prepend}_{idx})s)".format(
                idx=idx, prepend=prepend, prop_var=prop_var
            ),
            params,
        )
    elif operator == "icontains":
        value = "%{}%".format(prop.value)
        params = {"k{}_{}".format(prepend, idx): prop.key, "v{}_{}".format(prepend, idx): value}
        return (
            "AND trim(BOTH '\"' FROM JSONExtractRaw({prop_var}, %(k{prepend}_{idx})s)) LIKE %(v{prepend}_{idx})s".format(
                idx=idx, prepend=prepend, prop_var=prop_var
            ),
            params,
        )
    elif operator == "not_icontains":
        value = "%{}%".format(prop.value)
        params = {"k{}_{}".format(prepend, idx): prop.key, "v{}_{}".format(prepend, idx): value}
        return (
            "AND NOT (trim(BOTH '\"' FROM JSONExtractRaw({prop_var}, %(k{prepend}_{idx})s)) LIKE %(v{prepend}_{idx})s)".format(
                idx=idx, prepend=prepend, prop_var=prop_var
            ),
            params,