Refactor source API (#1846)

* refactor source API and syft json source block

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

* update source detection and format test utils

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

* generate list of all source metadata types

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

* extract base and root normalization into helper functions

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

* preserve syftjson model package name import ref

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

* alias should not be a pointer

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

---------

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

syft/formats/spdxjson/test-fixtures/snapshot/TestSPDXJSONDirectoryEncoder.golden

@@ -2,15 +2,15 @@
  "spdxVersion": "SPDX-2.3",
  "dataLicense": "CC0-1.0",
  "SPDXID": "SPDXRef-DOCUMENT",
- "name": "/some/path",
- "documentNamespace": "https://anchore.com/syft/dir/some/path-303fccb4-22d1-4039-9061-553bc875f086",
+ "name": "some/path",
+ "documentNamespace":"redacted",
  "creationInfo": {
-  "licenseListVersion": "3.20",
+  "licenseListVersion":"redacted",
   "creators": [
    "Organization: Anchore, Inc",
    "Tool: syft-v0.42.0-bogus"
   ],
-  "created": "2023-06-05T18:49:13Z"
+  "created":"redacted"
  },
  "packages": [
   {

syft/formats/spdxjson/test-fixtures/snapshot/TestSPDXJSONImageEncoder.golden

@@ -3,14 +3,14 @@
  "dataLicense": "CC0-1.0",
  "SPDXID": "SPDXRef-DOCUMENT",
  "name": "user-image-input",
- "documentNamespace": "https://anchore.com/syft/image/user-image-input-5b9aac79-334c-4d6a-b2e6-95a819c1d45a",
+ "documentNamespace":"redacted",
  "creationInfo": {
-  "licenseListVersion": "3.20",
+  "licenseListVersion":"redacted",
   "creators": [
    "Organization: Anchore, Inc",
    "Tool: syft-v0.42.0-bogus"
   ],
-  "created": "2023-06-05T18:49:14Z"
+  "created":"redacted"
  },
  "packages": [
   {

syft/formats/spdxjson/test-fixtures/snapshot/TestSPDXRelationshipOrder.golden

@@ -3,14 +3,14 @@
  "dataLicense": "CC0-1.0",
  "SPDXID": "SPDXRef-DOCUMENT",
  "name": "user-image-input",
- "documentNamespace": "https://anchore.com/syft/image/user-image-input-2a1392ab-7eb5-4f2a-86f6-777aef3232e1",
+ "documentNamespace":"redacted",
  "creationInfo": {
-  "licenseListVersion": "3.20",
+  "licenseListVersion":"redacted",
   "creators": [
    "Organization: Anchore, Inc",
    "Tool: syft-v0.42.0-bogus"
   ],
-  "created": "2023-06-05T18:49:14Z"
+  "created":"redacted"
  },
  "packages": [
   {