Make phpunit providers static

Author: firstred

tests/Misc/UtilTest.php

@@ -45,7 +45,7 @@ public function testGuzzleVersions($a, $b): void
     }
 
     /** @return array */
-    public function guzzleVersionProvider(): array
+    public static function guzzleVersionProvider(): array
     {
         return [
             [6, '6.0.0'],

tests/Service/LabellingServiceTest.php

@@ -667,7 +667,7 @@ public function testNegativeGenerateLabelInvalidResponseRest(ResponseInterface $
     /**
      * @return array[]
      */
-    public function singleLabelsProvider(): array
+    public static function singleLabelsProvider(): array
     {
         return [
             [PsrMessage::parseResponse(message: file_get_contents(filename: _RESPONSES_DIR_.'/rest/labelling/singlelabel.http'))],
@@ -679,7 +679,7 @@ public function singleLabelsProvider(): array
     /**
      * @return array[]
      */
-    public function multipleLabelsProvider(): array
+    public static function multipleLabelsProvider(): array
     {
         return [
             [