fixing w3c-tracecontext test startup

[brettmc]

make w3c-trace-context was suffering from some bitrot, so this change gets it building and
running again. The tests themselves still fail due to further code-related bitrot.

[codecov]

Codecov Report

Merging #668 (50e2e67) into main (4e32645) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##               main     #668   +/-   ##
=========================================
  Coverage     85.26%   85.26%           
  Complexity     1153     1153           
=========================================
  Files           128      128           
  Lines          2789     2789           
=========================================
  Hits           2378     2378           
  Misses          411      411           

Flag	Coverage Δ
7.4	85.21% <ø> (ø)
8.0	85.26% <ø> (ø)
8.1	85.26% <ø> (ø)

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