chore: revert 4c2ab943a8 (#1148)

Revert #1136 and use actionslib instead.

revert chore: bump the module path to `/v3`, take the version from the VCS stamp (#1136)

gitea can not consume the runner's api by version while it's version mismatches the module version:

```
go: gitea.com/gitea/runner@v3.0.1: invalid version: module contains a go.mod file,
so module path must match major version ("gitea.com/gitea/runner/v3")
```

Fix that by bumping the module version now. The existing `v3.0.0` and `v3.0.1` tags stay unusable, so a new tag is needed after this lands.

Also drop the version `-X` linker flags, which would otherwise have to repeat the new path in both `Makefile` and `.goreleaser.yaml`, where a stale path makes injection silently no-op. Go has recorded the module version in the build info since 1.24, so `Version()` reads it from there, keeping the variable as an override for builds without a VCS stamp.

That part started as https://gitea.com/gitea/runner/pulls/1137 but belongs here: the stamp resolves against the tags that are legal for the module path, so without the `/v3` bump it would report `v1.0.9-0.<ts>-<sha>`. Since `release-nightly.yml` triggers on every push to `main`, splitting them would publish a nightly with a `v1` version.

---------

Co-authored-by: bircni <bircni@icloud.com>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1136
Reviewed-by: techknowlogick <9+techknowlogick@noreply.gitea.com>
Reviewed-by: bircni <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1148
Reviewed-by: Zettat123 <39446+zettat123@noreply.gitea.com>

internal/app/cmd/bug_report.go

@@ -7,7 +7,7 @@ import (
 	"fmt"
 	"runtime"
 
-	"gitea.com/gitea/runner/v3/internal/pkg/ver"
+	"gitea.com/gitea/runner/internal/pkg/ver"
 
 	"github.com/spf13/cobra"
 )