Do not link test dependencies into main binary

[majst01]

Description

Imports in go files which are not named according to the go test naming convention _test.go will be included in the main binary. OTOH exported funcs in _test.go files can not be imported in other packages.

To circumvent this a build flag is introduced, which separates test code from production code.

This saves ~1Mb from the resulting binary and the testcontainers dependency can no longer be found like so:

$ strings bin/server | grep testcontainers

dep     github.com/testcontainers/testcontainers-go     v0.40.0 h1:pSdJYLOVgLE8YdUY2FHQ1Fxu+aMnb6JfVz1mxk7OeMU=
dep     github.com/testcontainers/testcontainers-go/modules/postgres    v0.38.0 h1:KFdx9A0yF94K70T6ibSuvgkQQeX1xKlZVF3hEagXEtY=
dep     github.com/testcontainers/testcontainers-go/modules/valkey      v0.40.0 h1:V0zwJVnN8fOT++ySwo/P5cwd3pmXI7O4VdA7kQ+5OiM=
github.com/testcontainers/testcontainers-go/internal/config.init
github.com/testcontainers/testcontainers-go/internal/core.init
github.com/testcontainers/testcontainers-go/internal/core.init.0
github.com/testcontainers/testcontainers-go/internal/core.init.1
github.com/testcontainers/testcontainers-go/log.init.0
github.com/testcontainers/testcontainers-go/log.noopLogger.Printf
github.com/testcontainers/testcontainers-go/log.(*noopLogger).Printf
github.com/testcontainers/testcontainers-go/wait.init
github.com/testcontainers/testcontainers-go.init
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/internal/config/config.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/internal/core/docker_host.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/internal/core/docker_socket.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/internal/core/images.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/internal/core/bootstrap.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/log/logger.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/wait/walk.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/docker.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/docker_mounts.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/docker_auth.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/port_forwarding.go
/home/stefan/go/pkg/mod/github.com/testcontainers/testcontainers-go@v0.40.0/testing.go
dep     github.com/testcontainers/testcontainers-go     v0.40.0 h1:pSdJYLOVgLE8YdUY2FHQ1Fxu+aMnb6JfVz1mxk7OeMU=
dep     github.com/testcontainers/testcontainers-go/modules/postgres    v0.38.0 h1:KFdx9A0yF94K70T6ibSuvgkQQeX1xKlZVF3hEagXEtY=
dep     github.com/testcontainers/testcontainers-go/modules/valkey      v0.40.0 h1:V0zwJVnN8fOT++ySwo/P5cwd3pmXI7O4VdA7kQ+5OiM=

[codecov]

Codecov Report

❌ Patch coverage is 0% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 69.74%. Comparing base (d05d29f) to head (40e477e).

Files with missing lines	Patch %	Lines
cmd/server/serve-cmd.go	0.00%	1 Missing ⚠️

❌ Your patch check has failed because the patch coverage (0.00%) is below the target coverage (25.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #108   +/-   ##
=======================================
  Coverage   69.74%   69.74%           
=======================================
  Files         130      130           
  Lines       10071    10071           
=======================================
  Hits         7024     7024           
  Misses       2329     2329           
  Partials      718      718           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.