Add script to generate proto on known version of protoc

[prodion23]

Description

Protobuf version was previously based on user installed version of proto(as mentioned here):
#165

This creates issues when trying to bump proto versions, as generating protobuf on a newer version limits our supported minimum, even though in requirements.txt and setup.py we specify a ceiling.

For some reason httpx needs added to dev dependencies(since Friday it seems like something has changed) and 3.7+ tests continue to hang indefinitely

[codecov]

Codecov Report

Merging #290 (bf885f3) into main (9ba081d) will increase coverage by 1.55%.
The diff coverage is 100.00%.

❗ Current head bf885f3 differs from pull request most recent head e8df9e2. Consider uploading reports for the commit e8df9e2 to get more accurate results

@@            Coverage Diff             @@
##             main     #290      +/-   ##
==========================================
+ Coverage   82.28%   83.84%   +1.55%     
==========================================
  Files          31       31              
  Lines        1558     1572      +14     
==========================================
+ Hits         1282     1318      +36     
+ Misses        276      254      -22     

Impacted Files	Coverage Δ
src/hypertrace/agent/config/config_pb2.py	100.00% <100.00%> (+31.88%)	⬆️
src/hypertrace/version.py	100.00% <100.00%> (ø)

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