Update gcp bom to 26.50.0

[damccorm]

This notably includes upgrading protobuf. Changes are segmented by commit:

• Update the bom with the bom updater script - e8b2c0a
• Remove null checks - 5762104 - this is because proto fields can no longer be null (they'll at least have a default implementation)
• Update google_cloud_bigdataoss_version - 4a5efdd - this is because gcsio was not compatible with Protobuf 4 until this release.
• Update aws client versions to be compatible with Protobuf 4 - b72d791

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[damccorm]

Some failures are caused because proto fields can no longer be null (they'll at least have a default implementation). Addressing this now

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[damccorm]

cc/ @ldetmer

[shunping]

LGTM

[Abacn]

It seems this breaks https://github.com/apache/beam/actions/workflows/beam_PostCommit_Java_Hadoop_Versions.yml?query=event%3Aschedule: #33252

[Abacn]

and https://github.com/apache/beam/actions/workflows/beam_PreCommit_Java_Debezium_IO_Direct.yml?query=event%3Aschedule also

[damccorm]

Thanks - #33525 should fix the first issue, working on a fix for the second

[Abacn]

Thanks, persumably debezium test is the same cause? (which could be trickier as we have conflict protobuf version for DebeziumIO then)

[damccorm]

Yeah, I'm seeing if I can upgrade our debezium dependency version. That does seem like a larger issue though

[damccorm]

One thing which may help is that the problematic dependency is actually a test-only dependency -

beam/sdks/java/io/debezium/build.gradle

Line 65 in 4a5575c

testImplementation group: 'io.debezium', name: 'debezium-connector-postgres', version: '1.3.1.Final'

- debezium-connector-postgres

So worst case, we could probably only force the dependency for testing postgres, but that is definitely not an awesome place to land...