Add Nix cataloger (#1696)

* Add Basic Nix Cataloger

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>

* Update nix def for the latest syft definition

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>

* capture nix package files on pkg.NixStoreMetadata

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

* fix unit tests and linting

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

* update JSON schema

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

* address review comments

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

* Update syft/pkg/cataloger/nix/parse_nix_store_path_test.go

Co-authored-by: Florian Klink <flokli@flokli.de>
Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

* support unstable version conventions

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

* update json schema relative to main branch

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

* update syft json with v7.1.1 schema

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

* fix CLI tests

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

* remove extra continue statement

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

* add Nix to list of supported ecosystems

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

---------

Signed-off-by: Julio Tain Sueiras <juliosueiras@gmail.com>
Signed-off-by: Alex Goodman <alex.goodman@anchore.com>
Co-authored-by: Julio Tain Sueiras <juliosueiras@gmail.com>
Co-authored-by: Florian Klink <flokli@flokli.de>

schema/json/generate.go

@@ -45,6 +45,7 @@ type artifactMetadataContainer struct {
 	Hackage           pkg.HackageMetadata
 	Java              pkg.JavaMetadata
 	KbPackage         pkg.KbPackageMetadata
+	Nix               pkg.NixStoreMetadata
 	NpmPackage        pkg.NpmPackageJSONMetadata
 	NpmPackageLock    pkg.NpmPackageLockJSONMetadata
 	MixLock           pkg.MixLockMetadata