Add grpc-adapter to spring-cloud-alibaba-dependencies

[tomasAlabes]

Describe what this PR does / why we need it

grpc-adapter is missing from the platform dependencies. If you use spring-cloud-alibaba-dependencies and need the grpc-adapter then you need to add the appropriate dependency version manually.

Does this pull request fix one issue?

NONE

Describe how you did it

Just added the missing dep

Describe how to verify it

Add grpc-adapter as dependency with the platform, the version for it should be resolved automatically.

Special notes for reviews

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