RSS reader never stops

[w3stling]

The PR fixes issue #170 causing the program never to stop.

Example:

public static void main(String[] args) throws IOException {
    RssReader rssReader = new RssReader();
    List<Item> items = rssReader.read(URL).toList();
}

Fixed by using daemon threads in the executor service

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[github-actions]

Test Results

  9 files    9 suites   31s ⏱️
149 tests 147 ✅ 2 💤 0 ❌
157 runs  155 ✅ 2 💤 0 ❌

Results for commit 0621893.