update parameters in `Job` functions

[IgnacioHeredia]

Just a little update on the parameters in deregister_job(). Tested it.

I choose Union instead of Optional for parameters in line with this.

[codecov[bot]]

Codecov Report

Merging #153 (2c8e250) into master (364f063) will increase coverage by 0.08%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #153      +/-   ##
==========================================
+ Coverage   90.63%   90.71%   +0.08%     
==========================================
  Files          31       31              
  Lines        1292     1293       +1     
==========================================
+ Hits         1171     1173       +2     
+ Misses        121      120       -1     

Impacted Files	Coverage Δ
nomad/api/job.py	94.52% <100.00%> (-0.08%)	:arrow_down:

... and 4 files with indirect coverage changes

[nikita-b]

@IgnacioHeredia Could you, please, fix the linters?

[IgnacioHeredia]

@nikita-b done!

[nikita-b]

LGTM, @IgnacioHeredia thanks for your contribution!

[nikita-b]

@IgnacioHeredia Oh, it seems we still have an issue with black formatter.

[IgnacioHeredia]

@nikita-b done!