[TASK] Remove TYPO3 9 support and prepare Upgrade.md

Upgrade.md

+# Upgrade from ```9.x.x``` to ```10.x.x```
+
+- Dropped TYPO3 9 support
+
 # Upgrade from ```8.x.x``` to ```9.x.x```
 
 - Dropped TYPO3 8 support

composer.json

@@ -16,7 +16,7 @@
         }
     ],
     "require": {
-        "typo3/cms-core": "^9.5.0 || ^10.4.0"
+        "typo3/cms-core": "^10.4.0"
     },
     "suggest": {
         "sgalinski/sg-ajax": "Required for the like feature",

ext_emconf.php

@@ -22,8 +22,8 @@ $EM_CONF['sg_news'] = [
 	'version' => '9.5.2',
 	'constraints' => [
 		'depends' => [
-			'typo3' => '9.5.0-10.4.99',
-			'php' => '7.3.0-7.4.99',
+			'typo3' => '10.4.99',
+			'php' => '7.4.99',
 		],
 		'conflicts' => [],
 		'suggests' => [