Update tonic, prost, and friends

[davidpdrsn]

Updates tonic and tonic-build to 0.6 and prost, prost-build, and prost-types to 0.8.

When building this locally I get this error:

error: failed to run custom build command for `opentelemetry-zpages v0.1.0 (opentelemetry-rust/opentelemetry-zpages)`

Caused by:
  process didn't exit successfully: `opentelemetry-rust/target/debug/build/opentelemetry-zpages-5a7a6985eea043c2/build-script-build` (exit status: 101)
  --- stderr
  thread 'main' panicked at 'protoc binary not found: cannot find binary path', ~/.cargo/registry/src/github.com-1ecc6299db9ec823/protoc-2.25.2/src/lib.rs:203:17
  note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

However I also get that main so not sure if its a an issue in my setup or a general issue.

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ David Pedersen (c4824ee, cdb3592, f1876e0)

[davidpdrsn]

I'm working on getting the CLA signed. I work at Embark Studios which have contributed before so shouldn't be too hard 🤞

[codecov]

Codecov Report

Merging #660 (d22fdf9) into main (9f3abed) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #660   +/-   ##
=======================================
  Coverage   71.39%   71.39%           
=======================================
  Files         101      101           
  Lines        8564     8564           
=======================================
  Hits         6114     6114           
  Misses       2450     2450           

Impacted Files	Coverage Δ
opentelemetry-otlp/src/span.rs	0.00% <ø> (ø)

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[TommyCpp]

Thanks! may need to run cargo fmt. The error was because opentelemetry-zpages uses grpcio for Grpc, it requires some dependencies. It's unrelated to your change so you should be good.

[lsunsi]

I'm interested in this!

[davidpdrsn]

Sorry for taking so long to finish this, but I have not forgotten about it 😅

However I've realized that tonic 0.6 switched to the 2021 edition which isn't compatible with opentelemetry's MSRV. So we have to move tonic back to 2018 first. I'm doing that here.

[jtescher]

@davidpdrsn looks good just one clippy lint left looks like

[davidpdrsn]

I just published tonic 0.6.2 which reverted to using rust 2018 so this can now be compatible with opentelemetry's MSRV. I'll update this PR tomorrow.

[davidpdrsn]

The lint error from CI seems to be unrelated to these changes. Let me know if you want me to address them somehow.

Otherwise this should be good to go now 😊

[lsunsi]

Thanks @davidpdrsn !

[jtescher]

@davidpdrsn mind rebasing (or letting otel maintainers edit your branch so we can rebase for you)? The otel org has set all repos to require up to date branches to be merged unfortunately

[davidpdrsn]

@jtescher doesn't seem like you can enable maintainer edits after creating the PR. I'll get this rebased within the next few days!

[jtescher]

@davidpdrsn ok thanks!

[djc]

@davidpdrsn the next release is coming soon. Do you have time to rebase this? (May need to open a new PR.)

[davidpdrsn]

@djc I rebased just now and it went clean through. 🤞 for CI