Add -upgrade to terraform init cmd

[ghostinthewires]

adding -upgrade to terraform init & get cmd as per #443

New to the project so not sure if this needs adding anywhere else. Just let me know if this isnt enough?

[codecov]

Codecov Report

Merging #495 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #495   +/-   ##
=======================================
  Coverage   70.65%   70.65%           
=======================================
  Files          63       63           
  Lines        4291     4291           
=======================================
  Hits         3032     3032           
  Misses       1031     1031           
  Partials      228      228

Impacted Files	Coverage Δ
server/events/runtime/init_step_runner.go	83.33% <100%> (ø)	⬆️

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