Examples: Update usage sections, fix some formatting and typos

[jfriedri-ni]

What does this Pull Request accomplish?

Helps new users run the examples.

Why should this Pull Request be merged?

Otherwise, the users need to read CONTRIBUTING.md to learn how to install the supporting packages.

What testing has been done?

The workflow checks.

[github-actions]

Test Results

   10 files  ± 0     10 suites  ±0   27s ⏱️ -4s
  221 tests + 5    221 ✅ + 5  0 💤 ±0  0 ❌ ±0 
2 160 runs  +50  2 160 ✅ +50  0 💤 ±0  0 ❌ ±0 

Results for commit d015966. ± Comparison against base commit 098c4b2.

This pull request removes 1 and adds 6 tests. Note that renamed tests count towards both.

tests.unit.test_panel_client ‑ test___get_unset_value___returns_not_found

tests.unit.test_convert ‑ test___none_value___to_any___raises_type_error
tests.unit.test_panel_client ‑ test___get_unset_value___raises_exception
tests.unit.test_panel_client ‑ test___try_get_unset_value___returns_none
tests.unit.test_python_panel_service_stub ‑ test___no_value___get_value___raises_exception
tests.unit.test_python_panel_service_stub ‑ test___no_value___try_get_value___gets_no_value
tests.unit.test_python_panel_service_stub ‑ test___set_value___try_get_value___gets_response

♻️ This comment has been updated with latest results.