Upgrade Go to 1.21

[JoshVanL]

This includes updating the Go ref in go.mod as well as selected Go versions in .github workflows.

Note that, due to the change in import and init func ordering changing in Go 1.21, the grpc proxy proto codec is no longer registered after the grpc internal proto codec definition, meaning the dapr custom definition will not be registered and will cause errors. The custom proto needs to be either re-registered at runtime, or change its name in order to fix this.

There is likely other errors which need resolving when upgrading to 1.21.

[JoshVanL]

/assign

[mukundansundar]

CLI upgrade PR dapr/cli#1331

[berndverst]

@JoshVanL you mentioned you'll do the runtime Go 1.21 migration correct?

I completed the contrib Go 1.21 migration: dapr/components-contrib#3251

We will not be able to pin contrib anymore until runtime is also migrated, so it's high priority now.

You may want to use the updated linter configuration from here: https://github.com/dapr/components-contrib/blob/main/.golangci.yml

For consistency, please switch to Golangci-lint v1.55.2 which we now use in contrib. You will need to switch linter version for Go 1.21 support.

[JoshVanL]

@berndverst that's right yeah I'll be taking this ticket and working on it now. Thanks for the info, this is a great help 🙏