fix phpunit deprecations & warnings

Author: ryancco

.gitignore

@@ -3,4 +3,4 @@ composer.phar
 composer.lock
 .DS_Store
 .idea/
-.phpunit.result.cache
+.phpunit.cache

phpunit.xml

@@ -1,16 +1,23 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" bootstrap="vendor/autoload.php" backupGlobals="false" backupStaticAttributes="false" colors="true" verbose="true" convertErrorsToExceptions="true" convertNoticesToExceptions="true" convertWarningsToExceptions="true" processIsolation="false" stopOnFailure="false" xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/9.3/phpunit.xsd">
-  <coverage>
-    <include>
-      <directory suffix=".php">src/</directory>
-    </include>
-  </coverage>
-  <testsuites>
-    <testsuite name="Renoki Co Test Suite">
-      <directory>tests</directory>
-    </testsuite>
-  </testsuites>
-  <php>
-    <server name="APP_ENV" value="testing"/>
-  </php>
+<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:noNamespaceSchemaLocation="vendor/phpunit/phpunit/phpunit.xsd"
+         bootstrap="vendor/autoload.php"
+         cacheDirectory=".phpunit.cache"
+         failOnRisky="true"
+         failOnWarning="true">
+    <testsuites>
+        <testsuite name="Renoki Co Test Suite">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+
+    <php>
+        <server name="APP_ENV" value="testing"/>
+    </php>
+
+    <source restrictNotices="true" restrictWarnings="true">
+        <include>
+            <directory>src</directory>
+        </include>
+    </source>
 </phpunit>

psalm.xml

@@ -2,6 +2,7 @@
 
 namespace RenokiCo\PhpK8s\Test;
 
+use PHPUnit\Framework\Attributes\DataProvider;
 use RenokiCo\PhpK8s\Exceptions\KubeConfigBaseEncodedDataInvalid;
 use RenokiCo\PhpK8s\Exceptions\KubeConfigClusterNotFound;
 use RenokiCo\PhpK8s\Exceptions\KubeConfigContextNotFound;
@@ -208,10 +209,8 @@ public function test_in_cluster_config()
         K8sResource::setDefaultNamespace('default');
     }
 
-    /**
-     * @dataProvider environmentVariableContextProvider
-     */
-    public function test_from_environment_variable(string $context = null, string $expectedDomain)
+    #[DataProvider('environmentVariableContextProvider')]
+    public function test_from_environment_variable(?string $context, string $expectedDomain)
     {
         $_SERVER['KUBECONFIG'] = __DIR__.'/cluster/kubeconfig.yaml::'.__DIR__.'/cluster/kubeconfig-2.yaml';