Slim down docker cache size (#3190)

* slim down docker cache size

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

* remove old centos images

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

* troubleshoot test failure

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

* fix wget version ref

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

* refactor caching mechanisms

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

* add cache cleanup steps

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

* simplify deleting cache

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

* fix first clone issue

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

* add tool dep

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

---------

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

syft/pkg/cataloger/gentoo/cataloger_test.go

@@ -64,7 +64,7 @@ func TestPortageCataloger(t *testing.T) {
 	var expectedRelationships []artifact.Relationship
 
 	pkgtest.NewCatalogTester().
-		FromDirectory(t, "test-fixtures/image-portage").
+		FromDirectory(t, "test-fixtures/layout").
 		Expects(expectedPkgs, expectedRelationships).
 		TestCataloger(t, NewPortageCataloger())