feat(core-flows,medusa,utils): promotion and campaign create/update endpoint (#6130)

what:

- adds create endpoint for promotions including workflows and endpoint (RESOLVES CORE-1678)
- adds update endpoint for promotions including workflows and endpoint (RESOLVES CORE-1679)
- adds create endpoint for campaigns including workflows and endpoint (RESOLVES CORE-1684)
- adds update endpoint for campaigns including workflows and endpoint (RESOLVES CORE-1685)

packages/utils/src/common/__tests__/get-selects-and-relations-from-object-array.spec.ts

@@ -0,0 +1,62 @@
+import { getSelectsAndRelationsFromObjectArray } from "../get-selects-and-relations-from-object-array"
+
+describe("getSelectsAndRelationsFromObjectArray", function () {
+  it("should return true or false for different types of data", function () {
+    const expectations = [
+      {
+        input: [
+          {
+            attr_string: "string",
+            attr_boolean: true,
+            attr_null: null,
+            attr_undefined: undefined,
+            attr_object: {
+              attr_string: "string",
+              attr_boolean: true,
+              attr_null: null,
+              attr_undefined: undefined,
+            },
+            attr_array: [
+              {
+                attr_object: {
+                  attr_string: "string",
+                  attr_boolean: true,
+                  attr_null: null,
+                  attr_undefined: undefined,
+                },
+              },
+              {
+                attr_object: {
+                  attr_string: "string",
+                },
+              },
+            ],
+          },
+        ],
+        output: {
+          selects: [
+            "attr_string",
+            "attr_boolean",
+            "attr_null",
+            "attr_undefined",
+            "attr_object.attr_string",
+            "attr_object.attr_boolean",
+            "attr_object.attr_null",
+            "attr_object.attr_undefined",
+            "attr_array.attr_object.attr_string",
+            "attr_array.attr_object.attr_boolean",
+            "attr_array.attr_object.attr_null",
+            "attr_array.attr_object.attr_undefined",
+          ],
+          relations: ["attr_object", "attr_array", "attr_array.attr_object"],
+        },
+      },
+    ]
+
+    expectations.forEach((expectation) => {
+      expect(getSelectsAndRelationsFromObjectArray(expectation.input)).toEqual(
+        expectation.output
+      )
+    })
+  })
+})