Manage context-propagation version in micrometer-bom

[shakuzen]

Projects that have instrumentation based on Micrometer Observation may also need to use context-propagation to ensure propagation in that project is handled correctly. Currently, as context-propagation is an optional dependency, there is no version management provided in this case. If the project depends on Micrometer Tracing, that will pull in a transitive dependency on context-propagation (eliminating the need to choose the version), but not every project will have a dependency on tracing.

We can add context-propagation to the micrometer-bom with the version that we compile against for our optional integration with context-propagation in micrometer-core.

[spencergibb]

So part of boot 3.3? So cloud will be able to use it with a boot 3.4 baseline in 2024.0

[shakuzen]

So part of boot 3.3?

Yes