feat: add project versions (#110)

* refactor: allow version matrixes by projects

* feat: add initial version-matrix for mage-os

* feat: add project as optional input to action

* docs: document new input

* refactor: tighten types a bit

* chore: apply change requests from code review

supported-version/src/project/validations/is-known-project.spec.ts

@@ -0,0 +1,13 @@
+import {isKnownProject} from "./is-known-project";
+import {Project} from "../projects";
+
+describe('isKnownProject', () => {
+  it('returns `true` for known projects', () => {
+      expect(isKnownProject("mage-os")).toBe(true)
+      expect(isKnownProject("magento-open-source")).toBe(true)
+  });
+
+  it('throws a message if for unknown projects', () => {
+      expect(() => isKnownProject(<Project>"bingo")).toThrowError()
+  });
+})