revert: drop the squash-only image read and bump stereoscope

stereoscope is replacing `image.WithImageSquashOnly` with lazy layer squashes, where every layer keeps a usable squash. That removes the need for `GetSourceConfig.WithImageSquashOnly` and the scope guard in `FileResolver`, so both go.

- bumps stereoscope to `feat/lazy-layer-squashes` (anchore/stereoscope `43c8f7e`), pending that PR merging

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

syft/source/stereoscopesource/image_source_provider_test.go

@@ -1,64 +0,0 @@
-package stereoscopesource
-
-import (
-	"context"
-	"path/filepath"
-	"testing"
-
-	"github.com/google/go-containerregistry/pkg/name"
-	"github.com/google/go-containerregistry/pkg/v1/random"
-	"github.com/google/go-containerregistry/pkg/v1/tarball"
-	"github.com/stretchr/testify/require"
-
-	"github.com/anchore/stereoscope"
-	"github.com/anchore/stereoscope/pkg/image"
-	"github.com/anchore/syft/syft/source"
-)
-
-func Test_stereoscopeImageSourceProvider_imageSquashOnly(t *testing.T) {
-	img, err := random.Image(1024, 3)
-	require.NoError(t, err)
-	tag, err := name.NewTag("localhost/squash-only:latest")
-	require.NoError(t, err)
-	archive := filepath.Join(t.TempDir(), "image.tar")
-	require.NoError(t, tarball.WriteToFile(archive, tag, img))
-
-	provide := func(t *testing.T, squashOnly bool) source.Source {
-		providers := Providers(ProviderConfig{
-			StereoscopeImageProviderConfig: stereoscope.ImageProviderConfig{UserInput: archive},
-			ImageSquashOnly:                squashOnly,
-		})
-		for _, p := range providers {
-			if p.Value.Name() != image.DockerTarballSource {
-				continue
-			}
-			src, err := p.Value.Provide(context.Background())
-			require.NoError(t, err)
-			t.Cleanup(func() { require.NoError(t, src.Close()) })
-			return src
-		}
-		t.Fatalf("no %s provider", image.DockerTarballSource)
-		return nil
-	}
-
-	tests := []struct {
-		name       string
-		squashOnly bool
-		scope      source.Scope
-		wantErr    require.ErrorAssertionFunc
-	}{
-		{name: "full read, squashed", scope: source.SquashedScope, wantErr: require.NoError},
-		{name: "full read, all layers", scope: source.AllLayersScope, wantErr: require.NoError},
-		{name: "full read, deep squashed", scope: source.DeepSquashedScope, wantErr: require.NoError},
-		{name: "squash only, squashed", squashOnly: true, scope: source.SquashedScope, wantErr: require.NoError},
-		// the per-layer resolvers would dereference the dropped layer squashes, so refuse up front
-		{name: "squash only, all layers", squashOnly: true, scope: source.AllLayersScope, wantErr: require.Error},
-		{name: "squash only, deep squashed", squashOnly: true, scope: source.DeepSquashedScope, wantErr: require.Error},
-	}
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			_, err := provide(t, tt.squashOnly).FileResolver(tt.scope)
-			tt.wantErr(t, err)
-		})
-	}
-}