[Enhancement] Upgrade jetcd-core to 0.7.7

[Pil0tXia]

Search before asking

• I had searched in the issues and found no similar issues.

Enhancement Request

Dependabot failed to upgrade io.etcd:jetcd-core from 0.3.0 to 0.8.2 in #4957.

As far as our existing CI process is concerned, the last available version is 0.7.x. To use 0.8.x, we would have to compile the etcd module separately and then bring it in via SPI. So we can upgrade to 0.7.7 first.

However, the CI fails with version 0.7.7, probably because there are references to deprecated APIs in our source code.

Describe the solution you'd like

Update deprecated usages.

Are you willing to submit PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct *

[pmupkin]

good