Ignore backslashes and whitespace in requirements (#501)

setup-uv gets confused when there are backslashes in `requirements.txt`.
This changes the regex to ignore backslashes.

---------

Co-authored-by: axm2 <>

__tests__/version/requirements-hashes-file.test.ts

@@ -0,0 +1,10 @@
+import { getUvVersionFromFile } from "../../src/version/resolve";
+
+import { expect, test } from "@jest/globals";
+
+test("ignores dependencies starting with uv", async () => {
+  const parsedVersion = getUvVersionFromFile(
+    "__tests__/fixtures/uv-in-requirements-hash-txt-project/requirements.txt",
+  );
+  expect(parsedVersion).toBe("0.8.3");
+});