Update workhorse's Gitaly client dependency to include DNS lookup change

What does this MR do and why?

Gitaly currently uses the deprecated grpc.DialContext, which requires dns: prefixes for DNS resolution. However, tls: addresses lose DNS resolution because the dns: prefix is stripped. This creates issues when connecting to hostnames over TLS.

The new grpc.NewClient solves this by enabling DNS resolution by default, even without dns: prefixes. For example, tls://mygitalynode.test:1234 will now correctly resolve DNS. Only addresses with a DNS authority still require dns:.

This commit replaces grpc.DialContext with grpc.NewClient to simplify connection handling and fix the DNS resolution issue. Since Gitaly wraps gRPC connection logic, the change only needs to be made in one place.

Update Gitaly client dependency to include DNS lookup change

In gitaly!7673 (merged), gitaly, Gitaly updated how the client dials connections, including changes to DNS lookups. This commit manually updates the Gitaly client dependency to include that change.

See gitaly#6674 (closed) for details.

References

Screenshots or screen recordings

Before	After

How to set up and validate locally

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.