Collect partial configs (partial config and ssh keys) before appying

[steiler]

fixing #1916 by collecting the partial config and ssh keys in a buffer before deploying it altogether.

[codecov]

Codecov Report

Attention: Patch coverage is 38.88889% with 11 lines in your changes are missing coverage. Please review.

Project coverage is 53.73%. Comparing base (f2b4a62) to head (d147574).
Report is 231 commits behind head on main.

❗ Current head d147574 differs from pull request most recent head e6ade6b. Consider uploading reports for the commit e6ade6b to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1919      +/-   ##
==========================================
+ Coverage   48.59%   53.73%   +5.13%     
==========================================
  Files         133      155      +22     
  Lines       12789    11276    -1513     
==========================================
- Hits         6215     6059     -156     
+ Misses       5870     4352    -1518     
- Partials      704      865     +161     

Files	Coverage Δ
nodes/vr_sros/sshKey.go	54.54% <0.00%> (ø)
nodes/vr_sros/vr-sros.go	40.26% <50.00%> (+39.68%)	⬆️

... and 125 files with indirect coverage changes