contrib/redis/rueidis: add Mode method support (v1.0.56)

[korECM]

What does this PR do?

This PR updates the dd-trace-go integration for rueidis (in contrib/redis/rueidis) to support the Mode() method recently added to the rueidis.Client interface. This resolves a compile-time error that occurred when using dd-trace-go with rueidis versions v1.0.56 and later.

Specifically, it:

1. Adds the Mode() rueidis.ClientMode method to the tracedClient wrapper.
2. Updates the github.com/redis/rueidis dependency in go.mod to version v1.0.56 to ensure the necessary interface method exists and to align with the fix.

Motivation

As reported in discussion #3347 , newer versions of the rueidis library (starting from v1.0.56, due to changes in rueidis) introduced a Mode() method to their Client interface. This caused our tracedClient wrapper, which embeds the rueidis.Client, to no longer satisfy the interface, resulting in compile-time failures for users attempting to use dd-trace-go with these updated rueidis versions.

This PR directly addresses the incompatibility by implementing the missing Mode() method on our wrapper, simply calling the underlying client's method.

Regarding the Dependency Update:

Implementing this fix required updating the rueidis dependency to v1.0.56. We acknowledge that bumping dependency versions can potentially impact users who rely on older versions or have specific dependency constraints in their projects.

However, the alternative was leaving the integration broken for all users wanting to use rueidis v1.0.56 or newer. Given that this prevents users from adopting recent library updates alongside dd-trace-go, we decided that updating the dependency and fixing the compilation issue was the necessary path forward to restore functionality for those users. We believe this addresses a more immediate and blocking problem. We encourage reviewers to consider this trade-off.

Related Discussion: #3347

Reviewer's Checklist

• Changed code has unit tests for its functionality at or near 100% coverage.
• System-Tests covering this feature have been added and enabled with the va.b.c-dev version tag.
• There is a benchmark for any new code, or changes to existing code.
• If this interacts with the agent in a new way, a system test has been added.
• Add an appropriate team label so this PR gets put in the right place for the release notes.
• Non-trivial go.mod changes, e.g. adding new modules, are reviewed by @DataDog/dd-trace-go-guild.
• For internal contributors, a matching PR should be created to the v2-dev branch and reviewed by @DataDog/apm-go.

[kakkoyun]

LGTM

[darccio]

Thanks @korECM. We are merging the changes contributed in a previous PR #3301. Closing this one in favour of that one.