Initial BPer implementation

test/support/utils.ts

@@ -0,0 +1,17 @@
+import * as core from "@actions/core";
+
+export const addProcessArgs = (args: string[]) => {
+  process.argv = [...process.argv, ...args];
+};
+
+export const resetProcessArgs = () => {
+  process.argv = ["node", "backporting"];
+};
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const spyGetInput = (obj: any) => {
+  const mock = jest.spyOn(core, "getInput");
+  mock.mockImplementation((name: string) : string => {
+    return obj[name];
+  });
+};