Move trace output earlier in state transition tests

[gumb0]

When I debug state transition tests, sometimes I want to see the trace even if this assertion fails

ASSERT_NE(acc, nullptr) << "account " << addr << " should exist";

[codecov]

Codecov Report

Merging #714 (604fe80) into master (74d2143) will not change coverage.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #714   +/-   ##
=======================================
  Coverage   97.60%   97.60%           
=======================================
  Files          95       95           
  Lines        8645     8645           
=======================================
  Hits         8438     8438           
  Misses        207      207           

Flag	Coverage Δ
blockchaintests	62.37% <ø> (ø)
statetests	73.47% <ø> (ø)
statetests-silkpre	22.64% <0.00%> (ø)
unittests	95.58% <100.00%> (ø)

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Files	Coverage Δ
test/unittests/state_transition.cpp	94.91% <100.00%> (ø)