fix: announce the change to repo versioning

[devjgm]

Part of #3615
Fixes: #3531

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This change is 

[codecov]

Codecov Report

Merging #3616 into master will increase coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3616      +/-   ##
==========================================
+ Coverage   92.09%   92.14%   +0.04%     
==========================================
  Files         458      458              
  Lines       41375    41341      -34     
==========================================
- Hits        38105    38093      -12     
+ Misses       3270     3248      -22

Impacted Files	Coverage Δ
.../cloud/storage/internal/resumable_upload_session.h	43.75% <0%> (-14.15%)	⬇️
google/cloud/bigtable/internal/common_client.h	89.47% <0%> (-10.53%)	⬇️
google/cloud/storage/internal/hash_validator.h	80% <0%> (-8.89%)	⬇️
google/cloud/storage/bucket_metadata.h	99.41% <0%> (-0.02%)	⬇️
google/cloud/storage/client_options.h	100% <0%> (ø)	⬆️
google/cloud/bigtable/row_range.h	100% <0%> (ø)	⬆️
.../cloud/storage/oauth2/compute_engine_credentials.h	100% <0%> (ø)	⬆️
google/cloud/storage/service_account.h	100% <0%> (ø)	⬆️
google/cloud/storage/object_metadata.h	100% <0%> (ø)	⬆️
google/cloud/bigtable/benchmarks/setup.h	100% <0%> (ø)	⬆️
... and 10 more

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