fix: Downgrade OkHttp 5.0.0-alpha.7 -> 4.10.0
fix: Downgrade OkHttp 5.0.0-alpha.7 -> 4.10.0

This change partially reverts the upgrade performed in #829, and is an
alternative fix for #816. OkHttp 4.10.0 depends on Kotlin 1.6.20, which
is not vulnerable to CVE-2020-29582.

This downgrade also resolves #832.

See:
- https://square.github.io/okhttp/changelogs/changelog_4x/#version-4100
- https://nvd.nist.gov/vuln/detail/CVE-2020-29582

googlemaps/google-maps-services-java