tests: Add OpenLineage to system tests in Google provider

[kacpermuda]

This PR adds checking OpenLineage events produced by selected Google Provider operators when running system checks. This is an addition to unit tests already checking OpenLineage for specific operators.

Thanks to VariableTransport introduced in #43643, we can easily check if OpenLineage events produced by any operator match the expected values. The logic is simple, for each system tests: adding the OpenLineageTestOperator to the DAG and providing it with json file with what we expect to be in the events. Whenever a system test is run, we will verify OpenLineage events emitted.

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[potiuk]

cc: @VladaZakharova - is that ok with you ?

[potiuk]

I merge it so that we can make provider move - but we can always remove / update if needed.