Deprecated nullable type causes a warning on PHP 8.4

[Marian-Kechlibar]

Describe the bug

This is a mostly self-explaining problem whose fix is, fortunately, very simple - literally one extra letter.

Deprecated: Microsoft\Graph\Core\Requests\BaseBatchRequestBuilder::__construct(): Implicitly marking parameter $errorMappings as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/microsoft/microsoft-graph-core/src/Requests/BaseBatchRequestBuilder.php on line 49

Looking at the signature of the constructor

public function __construct(RequestAdapter $requestAdapter, array $errorMappings = null)

should be

public function __construct(RequestAdapter $requestAdapter, ?array $errorMappings = null)

Maybe the whole codebase should be scanned for this deprecation... these will become errors in PHP 9.

Expected behavior

No deprecation warning.

How to reproduce

Run anything with this class under PHP 8.4

SDK Version

2.25.0

Latest version known to work for scenario above?

No response

Known Workarounds

No response

Debug output

Click to expand log

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</details>


### Configuration

_No response_

### Other information

_No response_

[Marian-Kechlibar]

So, here is more of them:

Deprecated: Microsoft\Graph\GraphRequestAdapter::__construct(): Implicitly marking parameter $httpClient as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/microsoft/microsoft-graph/src/GraphRequestAdapter.php on line 32

Deprecated: Microsoft\Graph\Core\GraphClientFactory::getDefaultHandlerStack(): Implicitly marking parameter $handler as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/microsoft/microsoft-graph-core/src/GraphClientFactory.php on line 146

Deprecated: Microsoft\Graph\Core\Requests\BaseBatchRequestBuilder::__construct(): Implicitly marking parameter $errorMappings as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/microsoft/microsoft-graph-core/src/Requests/BaseBatchRequestBuilder.php on line 49

Deprecated: Http\Promise\FulfilledPromise::then(): Implicitly marking parameter $onFulfilled as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/php-http/promise/src/FulfilledPromise.php on line 32

Deprecated: Http\Promise\FulfilledPromise::then(): Implicitly marking parameter $onRejected as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/php-http/promise/src/FulfilledPromise.php on line 32

Deprecated: Http\Promise\Promise::then(): Implicitly marking parameter $onFulfilled as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/php-http/promise/src/Promise.php on line 48

Deprecated: Http\Promise\Promise::then(): Implicitly marking parameter $onRejected as nullable is deprecated, the explicit nullable type must be used instead in /var/www/html/vendor/php-http/promise/src/Promise.php on line 48

[musale]

This will require updates in the various core libraries,