fix(deps): update dependency com.google.protobuf:protobuf-bom to v4

[renovate]

This PR contains the following updates:

Package	Change	Age	Adoption	Passing	Confidence
com.google.protobuf:protobuf-bom (source)	3.25.4 -> 4.28.2

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Release Notes

protocolbuffers/protobuf (com.google.protobuf:protobuf-bom)

v3.25.5

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Rebase checkbox removed since rebasing will cause custom changes to this PR to be lost.

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[breedx-splk]

I fiddled around with this for a while and couldn't get it working. It looks like the base class of generated messages changes (source?) and it seems like the toByteArray() (at least on grpc Status class) goes away.

[jack-berg]

It looks like the base class of generated messages changes (grpc/grpc-java#11015) and it seems like the toByteArray() (at least on grpc Status class) goes away.

The base class for messages changed from GeneratedMessageV3 to GeneratedMessage. The Status class comes from com.google.api.grpc:proto-google-common-protos, which hasn't upgraded to protobuf-bom v4 yet, and so there is a transitive dependency conflict which leads to the missing toByteArray method. We'll need to wait for com.google.api.grpc:proto-google-common-protos to upgrade, or maybe generate the classes ourselves if we're impatient, before upgrading.

Luckily, com.google.protobuf:protobuf-bom is only used in tests.

[jack-berg]

Looks like more work is still needed: protocolbuffers/protobuf#17247

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[jack-berg]

Two blockers stand in the way of merging this:

1. opentelemetry-proto-java still depends on an older version of grpc java. Need to bump those dependencies and cut a release: Bump grpc and protobuf versions opentelemetry-proto-java#17. Not clear how we cut a release since opentelemetry-proto-java versions are currently coupled to opentelemetry-proto releases.
2. Armeria has a transitive on grpc-version and has not yet upgraded to the 1.68.0 version which uses protobuf v4. This causes tests to fail which use armeria. Tracking issue: Compatibility with armeria and grpc 4.26.0 versions is broken. line/armeria#5504

Basically, we have to wait for all our dependencies which rely on grpc-java to upgrade to 1.68.0 and cut a release. Not clear if any others remain besides the two I've noted here. What a mess.