chore: improve ci

[giortzisg]

Description

This PR changes the ci pipeline to report codecov coverage only once, using the simplified makefile and also uses the native setup-go cache instead of a second dependency to improve ci speed.

Issues

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Reminders

• Add GH Issue ID & Linear ID
• PR title should use conventional commit style (feat:, fix:, ref:, meta:)
• For external contributors: CONTRIBUTING.md, Sentry SDK development docs, Discord community

[github-actions]

Semver Impact of This PR

🟢 Patch (bug fixes)

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Breaking Changes 🛠

• Update compatibility policy to align with Go, supporting only the last two major Go versions. by giortzisg in #1264
• Drop support for Go 1.24 by giortzisg in #1264

Internal Changes 🔧

Deps

• Bump github.com/labstack/echo/v5 from 5.0.0 to 5.0.3 in /echo by dependabot in #1253
• Bump github.com/labstack/echo/v5 from 5.0.0 to 5.0.3 in /crosstest by dependabot in #1272
• Bump golangci-lint action from 2.1.1 to 2.11.4 by giortzisg in #1265
• Bump go.opentelemetry.io/otel/sdk from 1.40.0 to 1.43.0 in /otel by dependabot in #1256
• Bump go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp from 1.40.0 to 1.43.0 in /otel/otlp by dependabot in #1255

Other

• Improve ci by giortzisg in #1271

• Add crosstest package by giortzisg in #1269
• Add sentrytest package by giortzisg in #1267

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[lcian]

I guess the test step implies make build?

[giortzisg]

we should actually keep build, for the slim case that we conditionally build a package (eg. //go:buildl !test)

[sentry]

Bug: The go test ... -coverprofile work command may fail when run against a workspace with multiple modules, potentially breaking the coverage reporting step in CI.
_{Severity: MEDIUM}

Suggested Fix

To guarantee that coverage is generated correctly, modify the test script to iterate through each module listed in the go.work file. Run go test with the -coverprofile flag for each module individually, generating separate coverage files. Afterwards, use a tool or a script to merge these individual coverage files into a single profile before the upload step.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent. Verify if this is a real issue. If it is, propose a fix; if not, explain why it's
not valid.

Location: .github/workflows/test.yml#L48

Potential issue: The CI workflow is configured to run `go test -coverprofile=... work`
to generate a unified code coverage report for a Go workspace containing 14 modules.
There is conflicting information on whether Go's tooling (specifically versions 1.25 and
1.26 used in the CI) supports the `-coverprofile` flag when testing multiple modules
simultaneously via the `work` keyword. If this operation is not supported, the test step
will fail for the `ubuntu` / `go 1.26` job, which is the only job responsible for
uploading coverage reports. This would cause the CI to either error out or silently fail
to produce coverage metrics.

_{Did we get this right? 👍 / 👎 to inform future reviews.}