python-jsonschema-specifications: Add new package

From the README:

JSON support files from the JSON Schema Specifications (metaschemas,
vocabularies, etc.), packaged for runtime access from Python as a
referencing-based Schema Registry.

Signed-off-by: Jeffery To <jeffery.to@gmail.com>

lang/python/python-jsonschema-specifications/test.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+
+[ "$1" = python3-jsonschema-specifications ] || exit 0
+
+python3 - << 'EOF'
+
+from jsonschema_specifications import REGISTRY as SPECIFICATIONS
+
+DRAFT202012_DIALECT_URI = "https://json-schema.org/draft/2020-12/schema"
+assert SPECIFICATIONS.contents(DRAFT202012_DIALECT_URI) != ""
+
+EOF