4371: Update --collect-only to display test descriptions when ran in verbose

[jeffreyrack]

This implements #4371 by updating --collect-only to display test descriptions when running in verbose mode.

Example output:

plugins: xdist-1.23.0, forked-0.2, env-0.6.2, hypothesis-3.73.4
collected 2 items
<Module example_description.py>
  Module containing tests.
  <Function test_a>
    This test has a description
  <Function test_b>
    This test has one docstring line.
    and a second one.

======================== no tests ran in 0.03 seconds =========================

(test_env) C:\Users\User\Desktop\pytest>

[RonnyPfannschmidt]

👍