Add source as parent node in CodeBase::addTaintSource()

[cgocast]

Fixes #10057

[cgocast]

This bugfix is not perfect but it is much simpler than #10206.

@orklah, please can you have a look at this PR ?

[Patrick-Remy]

Maybe both changes are required, in my PR I am also adding massive Taint-related tests and fixing examples.
Anyway, in my PR I still had issues that some taints weren't found where I hadn't found a solution for.
I will check if merging/applying your change into mine will fix the outstanding failing tests!

[cgocast]

Indeed my PR lacks taint-related tests and I agree we should merge your tests.

I am not convinced by the changes you made in the Analyzers. For instance, I was able to raise a TaintedHtml on

<?php // --taint-analysis

$foo = $bad_data;
echo $foo; 

without changing the Analyzers

[Patrick-Remy]

I now had time to test your changes and applied them to my original PR.
At least for me the test you mentioned is still failing.

And moreover, if I undo my other changes and just added the line you added, instead of the single test, 4 tests are failing

vendor/phpunit/phpunit/phpunit tests/Config/Plugin/EventHandler/AddTaints/AddTaintsInterfaceTest.php
PHPUnit 9.6.11 by Sebastian Bergmann and contributors.

Random Seed:   1719848602

FFF.F                                                               5 / 5 (100%)

Time: 00:05.312, Memory: 148.00 MB

There were 4 failures:

1) Psalm\Tests\Config\Plugin\EventHandler\AddTaints\AddTaintsInterfaceTest::testAddTaintsActiveRecord
Failed asserting that exception of type "Psalm\Exception\CodeException" is thrown.

2) Psalm\Tests\Config\Plugin\EventHandler\AddTaints\AddTaintsInterfaceTest::testTaintBadDataVariables
Failed asserting that exception of type "Psalm\Exception\CodeException" is thrown.

3) Psalm\Tests\Config\Plugin\EventHandler\AddTaints\AddTaintsInterfaceTest::testAddTaintsActiveRecordList
Failed asserting that exception of type "Psalm\Exception\CodeException" is thrown.

4) Psalm\Tests\Config\Plugin\EventHandler\AddTaints\AddTaintsInterfaceTest::testTaintsArePassedByTaintedAssignments
Failed asserting that exception of type "Psalm\Exception\CodeException" is thrown.

FAILURES!
Tests: 5, Assertions: 4, Failures: 4.

I will start rebasing my old branch and apply your commit as well, so that you can reproduce.

[Patrick-Remy]

Even rebased and with your commit applied, the test you mentioned is failing in the CI: https://github.com/vimeo/psalm/actions/runs/9747343000/job/26899836333?pr=10206

Therefor I will revert your change from my branch again, as mentioned in the PR description addTaintSource() was rewritten to immutability / purity. Adding again a side-effect there is a bit anti-design in my opinion.