Fix missing last line when kube err

[matoval]

This PR shows an issue reading last line when kube api returns an error because the error string doesn't end in a new line. The last line includes eof and never gets read.

I discovered this issue when getting failed to create fsnotify watcher: too many open files error in kube logs but receptor never got that error string.

We should look at refactoring way this file gets logs from kube api.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 9 lines in your changes missing coverage. Please review.

Project coverage is 40.49%. Comparing base (9243ccb) to head (38bbf4e).
Report is 3 commits behind head on devel.

Files with missing lines	Patch %	Lines
pkg/workceptor/kubernetes.go	0.00%	9 Missing ⚠️

@@            Coverage Diff             @@
##            devel    #1216      +/-   ##
==========================================
+ Coverage   39.93%   40.49%   +0.56%     
==========================================
  Files          45       48       +3     
  Lines        9266     9854     +588     
==========================================
+ Hits         3700     3990     +290     
- Misses       5289     5588     +299     
+ Partials      277      276       -1     

Files with missing lines	Coverage Δ
pkg/workceptor/kubernetes.go	21.41% <0.00%> (-0.14%)	⬇️

... and 6 files with indirect coverage changes

Components	Coverage Δ
Go	39.93% <0.00%> (+<0.01%)	⬆️
Receptorctl	49.31% <ø> (∅)

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[AaronH88]

lgtm