Improve get_best_match_zone() to match by most matched components instead of by length of domain

[monkut]

Description

Current get_best_match_zone() chooses the best match by length, so the expectation will result in error where a match is a partial match.

When zones are:

• example.com
• beta.example.com

And some-beta.example.com is given as the domain, the expected match is example.com, but beta.example.com will match.

This PR picks the zone with the most matches instead of length

GitHub Issues

#1190

[coveralls]

Coverage increased (+0.06%) to 74.472% when pulling 8058364 on feature-change/update-best-match-zone into 72c5dc3 on master.

[souravjamwal77]

Looks good.

[goya813]

Looks good p-r!!

I wanted the following test cases.

zone = Zappa.get_best_match_zone(
    all_zones={
        "HostedZones": [
            {
                "Name": "beta.example.com.",
                "Id": "zone-incorrect",
                "Config": {"PrivateZone": False},
            },
            {
                "Name": "example.com.",
                "Id": "zone-correct",
                "Config": {"PrivateZone": False},
            }
        ]
    },
    domain="example.com",
)

[monkut]

@goya813

Thanks for the review, nice catch!

I've added a testcase, and updated the code to account for that case.

[goya813]

Looks Good!