Add failing test for #4722

[CMTegner]

This issue describes a problem where snapshots are not correctly being matched against existing tests, causing duplicate snapshots to be written.

What does this PR do?

This PR adds a test that provokes the issue described in #4722.

How did you verify your code works?

$ bun-debug test test/regression/issue/04722.test.ts
<debug output omitted>
28 |         stderr: "pipe",
29 |         env: bunEnv,
30 |       });
31 |       expect(await testRun.exited).toBe(0);
32 |       const snapshotFile = file(join(testDir, "__snapshots__", `${filename}.snap`));
33 |       expect(await snapshotFile.text()).toBe('// Bun Snapshot v1, https://goo.gl/fbAQLP\n\nexports[`test 1`] = \`"\\\`${contents}\\\`"\`;\n');
                                             ^
error: expect(received).toBe(expected)

Expected: "// Bun Snapshot v1, https://goo.gl/fbAQLP\n\nexports[`test 1`] = `\"\\`${contents}\\`\"`;\n"
Received: "// Bun Snapshot v1, https://goo.gl/fbAQLP\n\nexports[`test 1`] = `\"\\`${contents}\\`\"`;\n\nexports[`test 1`] = `\"\\`${contents}\\`\"`;\n"

      at <redacted>/bun/test/regression/issue/04722.test.ts:33:41
      at asyncFunctionResume (:1:11)
      at promiseReactionJobWithoutPromiseUnwrapAsyncContext (:1:11)
      at promiseReactionJob (:1:11)
✗ existing snapshots are correctly parsed and matched against tests [78.82ms]

 0 pass
 1 fail
 4 expect() calls
Ran 1 tests across 1 files. [173.00ms]