Update the help text for the Pylint descriptor

The `msg-template` setting only works in the pylintrc configuration file
if it is under the `[REPORTS]` section header [0]. Otherwise the setting
gets ignored:
```
$ cat ./pylintrc
msg-template={path}:{module}:{line}: [{msg_id}({symbol}), {obj}] {msg}
$ pylint --rcfile=./pylintrc test.py
************* Module pylintrc
pylintrc:1:0: F0011: error while parsing the configuration: File contains no section headers.
file: 'pylintrc', line: 1
'msg-template={path}:{module}:{line}: [{msg_id}({symbol}), {obj}] {msg}\n' (config-parse-error)
[...]
```

Using the `--msg-template` CLI option is more convenient for the usage
inside Jenkins pipelines.

[0]: https://github.com/pylint-dev/pylint/blob/v2.17.4/examples/pylintrc#L481

src/main/java/edu/hm/hafner/analysis/registry/PyLintDescriptor.java

@@ -28,11 +28,8 @@ public IssueParser createParser(final Option... options) {
 
     @Override
     public String getHelp() {
-        return "<p>Create a ./pylintrc that contains:"
-                + "<p><code>msg-template={path}:{module}:{line}: [{msg_id}({symbol}), {obj}] {msg}</code></p>"
-                + "</p>"
-                + "<p>Start pylint using the command:"
-                + "<p><code>pylint --rcfile=./pylintrc CODE > pylint.log</code></p>"
+        return "<p>Start Pylint using this custom message template (can also be configured via a pylintrc configuration file):"
+                + "<p><code>pylint --msg-template='{path}:{line}: [{msg_id}, {obj}] {msg} ({symbol})' ... > pylint.log</code></p>"
                 + "</p>";
     }