docs(IConfig): fix wrong doc block type for `$key` on `setAppValue`

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

build/psalm-baseline.xml

@@ -3298,11 +3298,6 @@
       <code><![CDATA[ActivitySettings[]]]></code>
     </MoreSpecificReturnType>
   </file>
-  <file src="lib/private/AllConfig.php">
-    <MoreSpecificImplementedParamType>
-      <code><![CDATA[$key]]></code>
-    </MoreSpecificImplementedParamType>
-  </file>
   <file src="lib/private/App/DependencyAnalyzer.php">
     <InvalidNullableReturnType>
       <code><![CDATA[bool]]></code>

lib/public/IConfig.php

@@ -112,8 +112,8 @@ interface IConfig {
 	 * Writes a new app wide value
 	 *
 	 * @param string $appName the appName that we want to store the value under
-	 * @param string|float|int $key the key of the value, under which will be saved
-	 * @param string $value the value that should be stored
+	 * @param string $key the key of the value, under which will be saved
+	 * @param string|float|int $value the value that should be stored
 	 * @return void
 	 * @since 6.0.0
 	 * @deprecated 29.0.0 Use {@see IAppConfig} directly