fix(exec): dereference outputs container config for executor setup

[ecrupper]

This fixes an error where all executors try to share the outputs container config of whichever exec process last set it.

I'm also increasing the local stack build limit to 3 because this will help prevent future issues like this without sacrificing any sort of convenience for developers.

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 62.02%. Comparing base (04b2f56) to head (43c4aad).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
cmd/vela-worker/exec.go	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #612      +/-   ##
==========================================
- Coverage   62.02%   62.02%   -0.01%     
==========================================
  Files         121      121              
  Lines        8172     8173       +1     
==========================================
  Hits         5069     5069              
- Misses       2877     2878       +1     
  Partials      226      226              

Files with missing lines	Coverage Δ
cmd/vela-worker/exec.go	0.00% <0.00%> (ø)