Add Controller::owns_stream

[Dav1dde]

As shortly discussed on discord, this adds owns_stream and owns_stream_with to Controller to allowed customized watch streams for owned objects:

let sts_stream = watcher(Api::<StatefulSet>::all(client.clone()), watcher::Config::default())
    .touched_objects()
    .predicate_filter(predicates::generation);

Controller::new(Api::<CustomResource>::all(client), watcher::Config::default())
    .owns_stream(sts_stream)
    .run(reconcile, error_policy, Arc::new(()))
    .for_each(|_| std::future::ready(()))
    .await;

This patch depends on #911 for docs and is an extension to #1163 .

This can be used to aid stream sharing (#1080).

[codecov]

Codecov Report

Merging #1173 (2d8ecec) into main (61f2f32) will increase coverage by 0.15%.
The diff coverage is 68.54%.

❗ Current head 2d8ecec differs from pull request most recent head d59270d. Consider uploading reports for the commit d59270d to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1173      +/-   ##
==========================================
+ Coverage   72.43%   72.58%   +0.15%     
==========================================
  Files          65       67       +2     
  Lines        4759     5213     +454     
==========================================
+ Hits         3447     3784     +337     
- Misses       1312     1429     +117     

Impacted Files	Coverage Δ
kube-client/src/api/entry.rs	81.18% <0.00%> (-0.82%)	⬇️
kube-client/src/api/util/mod.rs	93.50% <ø> (+0.17%)	⬆️
kube-client/src/discovery/apigroup.rs	89.90% <0.00%> (ø)
kube-client/src/discovery/mod.rs	90.00% <ø> (ø)
kube-client/src/discovery/oneshot.rs	80.00% <ø> (ø)
kube-core/src/admission.rs	61.11% <ø> (ø)
kube-core/src/crd.rs	82.92% <ø> (ø)
kube-core/src/gvk.rs	82.60% <0.00%> (ø)
kube-core/src/schema.rs	89.70% <ø> (ø)
kube-core/src/subresource.rs	76.66% <ø> (ø)
... and 31 more

... and 7 files with indirect coverage changes

[clux]

minor nits, but looks good.

[clux]

Thanks a lot!