Webservice: Default to IPv4-only binds

What does this MR do?

Webservice: Default to IPv4-only binds

We enabled IPv6 support by default in #2778 (closed). After deploying this change to the staging environment, rate limiting unexpectedly began throttling unauthenticated requests.

To avoid affecting customers, we reverted to IPv4 bindings only until this bug has been fixed.

Related #6084

Changelog: changed

Related issues

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