worker: pass build environment to osbuild

Detect it from the host using the distro package.

internal/distro/distro.go

@@ -31,6 +31,9 @@ type Distro interface {
 	// output format with all packages and customizations specified in the
 	// given blueprint.
 	Pipeline(b *blueprint.Blueprint, outputFormat string) (*pipeline.Pipeline, error)
+
+	// Returns a osbuild runner that can be used on this distro.
+	Runner() string
 }
 
 var registered map[string]Distro

internal/distro/fedora30/distro.go

@@ -343,6 +343,10 @@ func (r *Fedora30) Pipeline(b *blueprint.Blueprint, outputFormat string) (*pipel
 	return p, nil
 }
 
+func (r *Fedora30) Runner() string {
+	return "org.osbuild.fedora30"
+}
+
 func (r *Fedora30) buildPipeline() *pipeline.Pipeline {
 	packages := []string{
 		"dnf",

internal/distro/rhel82/distro.go

@@ -373,6 +373,10 @@ func (r *RHEL82) Pipeline(b *blueprint.Blueprint, outputFormat string) (*pipelin
 	return p, nil
 }
 
+func (r *RHEL82) Runner() string {
+	return "org.osbuild.rhel82"
+}
+
 func (r *RHEL82) buildPipeline() *pipeline.Pipeline {
 	packages := []string{
 		"dnf",

internal/distro/test/distro.go

@@ -36,3 +36,7 @@ func (d *TestDistro) FilenameFromType(outputFormat string) (string, string, erro
 func (d *TestDistro) Pipeline(b *blueprint.Blueprint, outputFormat string) (*pipeline.Pipeline, error) {
 	return nil, errors.New("invalid output format: " + outputFormat)
 }
+
+func (d *TestDistro) Runner() string {
+	return "org.osbuild.test"
+}