Small bugfixes

[jordic]

• Don't brake swagger endpoints with services without explicit security declarations.
• Be able to use pgcatalog without a request (from commands for example)
• Cleanup old death code on shell command

[codecov-io]

Codecov Report

Merging #829 into master will increase coverage by 0.1%. The diff coverage is 100%.

@@           Coverage Diff            @@
##           master    #829     +/-   ##
========================================
+ Coverage    94.3%   94.3%   +0.1%     
========================================
  Files         312     312             
  Lines       28257   28257             
========================================
+ Hits        26642   26643      +1     
+ Misses       1615    1614      -1

Impacted Files	Coverage Δ
guillotina/contrib/catalog/pg.py	81.5% <ø> (+0.2%)	:arrow_up:
guillotina/contrib/swagger/services.py	91.8% <100%> (+0.1%)	:arrow_up: