refactor: use remote proto

[MichaelScofield]

I hereby agree to the terms of the GreptimeDB CLA

What's changed and what's your intention?

Move protobuf files to a common place (our new repo "https://github.com/GreptimeTeam/greptime-proto/") is a best practice for sharing them with our Java SDK and Go cloud projects.

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.

Refer to a related PR or issue link (optional)

close #585

[codecov]

Codecov Report

Merging #963 (73b82d1) into develop (70edd4d) will decrease coverage by 0.42%.
The diff coverage is 80.12%.

@@             Coverage Diff             @@
##           develop     #963      +/-   ##
===========================================
- Coverage    86.25%   85.84%   -0.42%     
===========================================
  Files          457      456       -1     
  Lines        61696    61827     +131     
===========================================
- Hits         53217    53075     -142     
- Misses        8479     8752     +273     

Flag	Coverage Δ
rust	85.84% <80.12%> (-0.42%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/api/src/lib.rs	100.00% <ø> (ø)
src/api/src/helper.rs	91.48% <75.96%> (ø)
src/api/src/v1/column_def.rs	100.00% <100.00%> (ø)
src/common/grpc-expr/src/alter.rs	94.17% <100.00%> (-0.07%)	⬇️
src/common/grpc/src/writer.rs	87.62% <100.00%> (ø)
src/datanode/src/server/grpc.rs	98.85% <100.00%> (ø)
src/frontend/src/instance/distributed.rs	89.09% <100.00%> (-0.02%)	⬇️
src/frontend/src/table/insert.rs	96.50% <100.00%> (ø)
src/object-store/src/test_util.rs	0.00% <0.00%> (-100.00%)	⬇️
src/common/substrait/src/df_expr.rs	30.81% <0.00%> (-15.91%)	⬇️
... and 19 more

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[fengjiachun]

lgtm