feat: use JSON proto for transaction-runner

[alexander-fenster]

Uses JSON proto load instead of GoogleProtoFilesRoot to load a proto for RetryInfo. Also, updates the JSON proto to include google/rpc/error_details.proto.

• Tests and linter pass
• Code coverage does not decrease (if any source code was changed)
• Appropriate docs were updated (if necessary)

[codecov]

Codecov Report

Merging #690 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #690      +/-   ##
==========================================
- Coverage   99.03%   99.03%   -0.01%     
==========================================
  Files          12       12              
  Lines        1350     1349       -1     
  Branches      213      213              
==========================================
- Hits         1337     1336       -1     
  Misses          4        4              
  Partials        9        9

Impacted Files	Coverage Δ
src/transaction-runner.ts	98.73% <100%> (-0.02%)	⬇️

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