Add proper support for Any in gRPC queries

[aaronc]

The initial PR's for gRPC (#6325, #6342) missed adding support for Any via AnyUnpacker/InterfaceRegistry. This PR adds:

• support for unpacking Anys in requests via the GRPCQueryRouter.SetAnyUnpacker() method
• support for unpacking Anys in CLI query calls via client.Context.InterfaceRegistry

Needed by #6593 and likely other PRs such as #6491.

/cc @blushi

---

Before we can merge this PR, please make sure that all the following items have been
checked off. If any of the checklist items are not applicable, please leave them but
write a little note why.

• Targeted PR against correct branch (see CONTRIBUTING.md)
• Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
• Code follows the module structure standards.
• Wrote unit and integration tests
• Updated relevant documentation (docs/) or specification (x/<module>/spec/)
• Added relevant godoc comments.
• Added a relevant changelog entry to the Unreleased section in CHANGELOG.md
• Re-reviewed Files changed in the Github PR explorer
• Review Codecov Report in the comment section below once CI passes

[codecov]

Codecov Report

Merging #6594 into master will decrease coverage by 0.03%.
The diff coverage is 51.11%.

@@            Coverage Diff             @@
##           master    #6594      +/-   ##
==========================================
- Coverage   57.21%   57.18%   -0.04%     
==========================================
  Files         481      481              
  Lines       28985    29015      +30     
==========================================
+ Hits        16585    16593       +8     
- Misses      11221    11241      +20     
- Partials     1179     1181       +2     

[fedekunze]

LGTM

[alexanderbez]

ACK