BLD: make containers only build on bilby-dev

[ColmTalbot]

I've seen emails from build jobs failing on forks, we should just builds everywhere except bilby-dev/bilby.

This change will mean that if we want to build from an unmerged branch, we will need that branch to be pushed to bilby-dev.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 66.23%. Comparing base (0985f75) to head (bc45bbb).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1058   +/-   ##
=======================================
  Coverage   66.23%   66.23%           
=======================================
  Files          89       89           
  Lines       17064    17064           
  Branches     2642     2642           
=======================================
  Hits        11303    11303           
  Misses       5021     5021           
  Partials      740      740           

Flag	Coverage Δ
python310	66.03% <ø> (ø)
python311	66.23% <ø> (ø)
python312	66.19% <ø> (-0.02%)	⬇️
python313	66.23% <ø> (+0.01%)	⬆️

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