Add kube::Api::get_metadata_opt_with

[sebsoto]

Adds the aforementioned method, allowing the use of get_metadata_opt() with an explicit ResourceVersion. This follows an existing pattern, as both get() and get_metadata() have *_with() variants.

Motivation

Addresses #1698

Solution

Adds kube::Api::get_metadata_opt_with

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.

Project coverage is 75.8%. Comparing base (a0c043a) to head (e500a99).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
kube-client/src/api/core_methods.rs	0.0%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #1708     +/-   ##
=======================================
- Coverage   75.8%   75.8%   -0.0%     
=======================================
  Files         84      84             
  Lines       7745    7746      +1     
=======================================
  Hits        5866    5866             
- Misses      1879    1880      +1     

Files with missing lines	Coverage Δ
kube-client/src/api/core_methods.rs	72.4% <0.0%> (-0.9%)	⬇️

[clux]

LGTM. Thank you!