If a run has been claimed, move work order from "pending" to "running"

[taylordowns2000]

This is likely to be super contentious, but the reality is that once it's claimed, we CANNOT STOP IT or get it back.

It can no longer be "cancelled". From the perspective of Lightning it's running, and we can't stop it.

Closes #4635

Validation steps

(Roina, can you show me how to find that edge case?)

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.62%. Comparing base (f8a1f0b) to head (c7c467d).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4637      +/-   ##
==========================================
- Coverage   89.63%   89.62%   -0.02%     
==========================================
  Files         444      444              
  Lines       21558    21558              
==========================================
- Hits        19324    19321       -3     
- Misses       2234     2237       +3     

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