With PhpUnit 10 came the ability to use Php attributes rather than doc-block annotations for things like "data provider". PhpUnit 11 deprecates the use of annotations, and PhpUnit 12 will not not permit their use. Since PhpUnit 11 requires Php8.2+, we cannot adopt it as long as we support Php8.1, which will continue to be the case for some time. However, there is no penalty for early adoption.
Php-cs-fixer can use:
```
'php_unit_attributes' => ['keep_annotations' => false],
```
This allows us to run `composer fix` to automate all the needed changes. No manual changes were needed for any of the test members.
With this change, PhpUnit 9 can no longer be used with the test suite. File composer.json is updated to reflect that reality, and phpunit9.xml.dist, which has been supplied in case anyone needed to use PhpUnit 9, is no longer required, and is thus deleted. For now, PhpUnit 11 is not being added as a possibility.
No source code is changed in this PR.
Till now we have used a static variable/getter/setter to decide what type of result should be returned when a formula is evaluated and an array is the result. This is messy; it would be much better to use an instance variable instead. We cannot eliminate `setArrayReturnType` and `getArrayReturnType` because that would be a BC break. I am considering whether they should be deprecated. In the meantime, I have added a new instance property `instanceArrayReturnType` with getter and setter methods. The property is initially null, and, if it remains so when needed, the static property will be used instead. However, if it is set, its value will be used.
SINGLE function can be used to return first value from a dynamic array result, or to return the value of the cell which matches the current row (VALUE error if not match) for a range. Excel allows you to specify an at-sign unary operator rather than SINGLE function; this PR does not permit that.
Add support for reading CSE array functions for Gnumeric.
Throw an exception if setValueExplicit Formula is invalid (not a string, or doesn't begin with equal sign. This is equivalent to what happens when setValueExplicit Numeric specifies a non-numeric value.
Added a number of tests from PR #2787.