fix(kubernetes_logs source): Set user-agent for k8s apiserver request…

…s. (#21905)

* fix(kubernetes_log source): Set user-agent for k8s apiserver requests.

* Update changelog.d/21864_kubernetes_logs_user_agent.fix.md

Co-authored-by: Pavlos Rontidis <[email protected]>

* Switch away from deprecated structs

* Update 21864_kubernetes_logs_user_agent.fix.md

* Try manually updating version via crate update

* Specify using tilde in Cargo.toml

* Rip out unused aws-runtime dep

* Try to limit dep bumps

* Revert superfluous import change

* Remove superfluous pins

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Co-authored-by: Orri Ganel <[email protected]>
Co-authored-by: Pavlos Rontidis <[email protected]>