[php] Configure Psalm 6 default settings findUnusedBaselineEntry, findUnusedCode

[olleolleolle]

🤔 What's changed?

Psalm's offering news, and our CI had not configured those settings.

This PR fixes a warning that outputs that we should be explicit about this setting.

First, I picked enabling it as the solution. (And, then I continued on that path.)

Psalm in CI: found some issues: 9 errors found

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Error: src/AstNode.php:38:37: UnusedParam: Param #1 is never referenced in this method (see https://psalm.dev/135)
Error: src/GherkinParser.php:31:31: UnusedProperty: Cannot find any references to private property Cucumber\Gherkin\GherkinParser::$predictableIds (see https://psalm.dev/150)
Error: src/GherkinParser.php:46:21: PossiblyUnusedMethod: Cannot find any calls to method Cucumber\Gherkin\GherkinParser::parseString (see https://psalm.dev/087)
Error: src/Location.php:15:21: PossiblyUnusedMethod: Cannot find any calls to method Cucumber\Gherkin\Location::getColumn (see https://psalm.dev/087)
Error: src/Parser/ParserTrait.php:76:16: UnusedReturnValue: The return value for this private method is never used (see https://psalm.dev/272)
Error: src/ParserException/UnexpectedEofException.php:16:31: PossiblyUnusedProperty: Cannot find any references to property Cucumber\Gherkin\ParserException\UnexpectedEofException::$receivedToken (see https://psalm.dev/149)
Error: src/ParserException/UnexpectedEofException.php:17:31: PossiblyUnusedProperty: Cannot find any references to property Cucumber\Gherkin\ParserException\UnexpectedEofException::$expectedTokenTypes (see https://psalm.dev/149)
Error: src/ParserException/UnexpectedEofException.php:18:32: PossiblyUnusedProperty: Cannot find any references to property Cucumber\Gherkin\ParserException\UnexpectedEofException::$stateComment (see https://psalm.dev/149)
Error: src/ParserException/UnexpectedTokenException.php:19:32: PossiblyUnusedProperty: Cannot find any references to property Cucumber\Gherkin\ParserException\UnexpectedTokenException::$stateComment (see https://psalm.dev/149)
------------------------------
9 errors found
------------------------------
Psalm can automatically fix 3 of these issues.
Run Psalm again with 
--alter --issues=PossiblyUnusedMethod,MissingParamType --dry-run
to see what it can fix.
------------------------------

Checks took 3.46 seconds and used 110.339MB of memory
Psalm was able to infer types for 100% of the codebase
Error: Process completed with exit code 2.

OK, so perhaps "enable" wasn't the right way, let's see if disabling will lead to nicer output? I learned a little, and placed some Psalm annotations in the code, in order to tell Psalm "these properties on the exceptions, they're expected, across all our implementations".

That got us a shorter list of Psalm offenses.

Psalm in CI: 5 errors found

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Error: src/AstNode.php:38:37: UnusedParam: Param #1 is never referenced in this method (see https://psalm.dev/135)
Error: src/GherkinParser.php:31:31: UnusedProperty: Cannot find any references to private property Cucumber\Gherkin\GherkinParser::$predictableIds (see https://psalm.dev/150)
Error: src/GherkinParser.php:46:21: PossiblyUnusedMethod: Cannot find any calls to method Cucumber\Gherkin\GherkinParser::parseString (see https://psalm.dev/087)
Error: src/Location.php:15:21: PossiblyUnusedMethod: Cannot find any calls to method Cucumber\Gherkin\Location::getColumn (see https://psalm.dev/087)
Error: src/Parser/ParserTrait.php:76:16: UnusedReturnValue: The return value for this private method is never used (see https://psalm.dev/272)
------------------------------
5 errors found
------------------------------

Upon thinking about those issues reported, I sort of think that it can absolutely be that it's part of the API to have some unused parameters (in code like AST handling callbacks). So, perhaps they're all @psalm-api.

⚡️ What's your motivation?

CI output should be terse, clear and focused. This change hopes to make it less noisy.

🏷️ What kind of change is this?

• 🏦 Refactoring/debt/DX (improvement to code design, tooling, documentation etc. without changing behaviour)

• I agree to respect and uphold the Cucumber Community Code of Conduct

[mpkorstanje]

I'd put these on to false. To get some warnings out of the way and then tackle what is left piece meal. Especially in the generated code it will be hard to follow psalms recommendations.

[olleolleolle]

I did put them to false, which didn't change the output. That confused me, so I continued on the track "follow the suggestions".

[mpkorstanje]

Weird. I can't reproduce that locally. Pushed a commit to see if it matters.

[olleolleolle]

@mpkorstanje This is super! Thanks for bringing it over the line. A lot less output!

[olleolleolle]

There!