v1.18: default staked client in LocalCluster (backport of #716)

[mergify]

Problem

• local cluster tests in CI slow since BankingStage Forwarding Filter #685

Summary of Changes

• LocalCluster connection cache defaults to use a client id with stake override to treat it like staked connection

Fixes #

---

This is an automatic backport of pull request #716 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of e91a5e2 has failed:

On branch mergify/bp/v1.18/pr-716
Your branch is up to date with 'origin/v1.18'.

You are currently cherry-picking commit e91a5e2744.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Changes to be committed:
	modified:   local-cluster/src/local_cluster.rs

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   local-cluster/tests/local_cluster.rs

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 81.5%. Comparing base (7b8ed3b) to head (945216b).

Additional details and impacted files

@@            Coverage Diff            @@
##            v1.18     #724     +/-   ##
=========================================
- Coverage    81.5%    81.5%   -0.1%     
=========================================
  Files         827      827             
  Lines      224833   224833             
=========================================
- Hits       183453   183418     -35     
- Misses      41380    41415     +35