Fix metrics for fallback jobs

[mjh1]

Since we're re-using the job object now we need to save to the db in the foreground go-routine to avoid picking up values from the fallback job

[codecov]

Codecov Report

Merging #854 (aa42440) into main (c81f282) will not change coverage.
The diff coverage is 100.00000%.

@@              Coverage Diff              @@
##                main        #854   +/-   ##
=============================================
  Coverage   51.66228%   51.66228%           
=============================================
  Files             63          63           
  Lines           6076        6076           
=============================================
  Hits            3139        3139           
  Misses          2685        2685           
  Partials         252         252           

Files Changed	Coverage Δ
pipeline/coordinator.go	80.61466% <100.00000%> (ø)

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Files Changed	Coverage Δ
pipeline/coordinator.go	80.61466% <100.00000%> (ø)

[thomshutt]

LGTM but linting isn't happy