test_runner: add mock return, resolve, reject and throw shorthands

[araujogui]

Adds mockReturnValue(), mockResolvedValue(), mockRejectedValue() and mockThrownValue() to MockFunctionContext as shorthands for common mockImplementation() patterns, matching the equivalent Jest/Vitest APIs.

fn.mock.mockReturnValue(42);
fn.mock.mockResolvedValue(42);
fn.mock.mockRejectedValue(new Error('boom'));
fn.mock.mockThrownValue(new Error('boom'));

[nodejs-github-bot]

Review requested:

• @nodejs/test_runner

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.49%. Comparing base (7514ef8) to head (7460a66).
⚠️ Report is 60 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66631      +/-   ##
==========================================
- Coverage   92.79%   90.49%   -2.30%     
==========================================
  Files         422      791     +369     
  Lines      193669   277122   +83453     
  Branches    29886    53285   +23399     
==========================================
+ Hits       179712   250783   +71071     
- Misses      13630    16752    +3122     
- Partials      327     9587    +9260     

Files with missing lines	Coverage Δ
lib/internal/test_runner/mock/mock.js	97.40% <100.00%> (+0.52%)	⬆️

... and 513 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/78344/