Document WAR containerization with jetty

[chanseokoh]

Helps with #3204.

[codecov]

Codecov Report

Merging #3205 (ffca39c) into master (75a3326) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master    #3205   +/-   ##
=========================================
  Coverage     71.24%   71.24%           
  Complexity     2328     2328           
=========================================
  Files           279      279           
  Lines          9844     9844           
  Branches        977      977           
=========================================
  Hits           7013     7013           
  Misses         2493     2493           
  Partials        338      338           

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 75a3326...ffca39c. Read the comment docs.