Support RPM distros with newer RPM db formats (#1018)

* Support RPM distros with newer db formats

Recent RPM distros (Fedora 33+, CBL-Mariner 2.0+, amazonlinux 2022+)
use an sqlite package database in /var/lib/rpm/rpmdb.sqlite, or
"ndb" format (SUSE).

Remove anchore's fork in favour of the upstream,
https://github.com/knqyf263/go-rpmdb, to gain support for
these formats.

Signed-off-by: Tom Fay <tomfay@microsoft.com>

* add exception for modernc.org repos

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* shorten rpmdb helper function

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

Co-authored-by: Alex Goodman <alex.goodman@anchore.com>

test/integration/sqlite_rpmdb_test.go

@@ -0,0 +1,25 @@
+package integration
+
+import (
+	"testing"
+
+	"github.com/anchore/syft/syft/source"
+
+	"github.com/anchore/syft/syft/pkg"
+)
+
+func TestSqliteRpm(t *testing.T) {
+	// This is a regression test for issue #469 (https://github.com/anchore/syft/issues/469). Recent RPM
+	// based distribution store package data in an sqlite database
+	sbom, _ := catalogFixtureImage(t, "image-sqlite-rpmdb", source.SquashedScope)
+
+	expectedPkgs := 139
+	actualPkgs := 0
+	for range sbom.Artifacts.PackageCatalog.Enumerate(pkg.RpmPkg) {
+		actualPkgs += 1
+	}
+
+	if actualPkgs != expectedPkgs {
+		t.Errorf("unexpected number of RPM packages: %d != %d", expectedPkgs, actualPkgs)
+	}
+}

test/integration/test-fixtures/image-sqlite-rpmdb/Dockerfile

@@ -0,0 +1 @@
+FROM fedora:35@sha256:36af84ba69e21c9ef86a0424a090674c433b2b80c2462e57503886f1d823abe8