Update Tower dependency to 0.4.9

[jvff]

Motivation

This is part of the update to use Tokio version 1 (#2200), and must be merged together with the other PRs.

The Tower crate has to be updated to a version that is compatible with the newer version of Tokio. No changes are actually necessary for the update. However, the ServiceExt::ready_and function became deprecated and that makes the build produce a lot of warnings.

Solution

The Tower dependency was updated to 0.4.9, which allows removal of the patched dependency. In order to remove all of the warnings, all usages of ServiceExt::ready_and were replaced with usages of ServiceExt::ready.

Review

Anyone from the team can review this PR, but it shouldn't be merged yet.

Reviewer Checklist

• Code implements Specs and Designs
• Tests for Expected Behaviour
• Tests for Errors

Follow Up Work

[dconnolly]

Should this be pointed at #2920 as a base?

[jvff]

Should this be pointed at #2920 as a base?

I don't know how to change the base 😓

But it shouldn't matter I think, it will still depend on a few other PRs as well :/

[teor2345]

I don't know how to change the base 😓

When you're editing the PR name, the base change menu is here:

But it shouldn't matter I think, it will still depend on a few other PRs as well :/

It only really matters when you have changes from multiple PRs in the GitHub diff.

Since we're not merging these PRs, we don't have to get the tests to pass, so it's not as important.

[jvff]

When you're editing the PR name, the base change menu is here:

Awesome, thanks!

Since we're not merging these PRs, we don't have to get the tests to pass, so it's not as important.

Ok, cool 👍

[conradoplg]

Seem good!This confirms that it's just a rename https://github.com/tower-rs/tower/releases/tag/tower-0.4.6

(I'm just taking a look so I'll leave approval for the reviewers assigned)

[teor2345]

This looks good.

[dconnolly]

lgtm!

[jvff]

Merged through #2994.