Drop PHP7.3

Signed-off-by: Christoph Wurst <christoph@winzerhof-wurst.at>

composer.json

 		"optimize-autoloader": true,
 		"sort-packages": true,
 		"platform": {
-			"php": "7.3"
+			"php": "7.4"
 		},
 		"allow-plugins": {
 			"bamarni/composer-bin-plugin": true

composer.lock

         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "eb074699155bba86b710218a07fe659b",
+    "content-hash": "8333c8a239fe5ccec285dfbccc17cca4",
     "packages": [],
     "packages-dev": [
         {
     },
     "platform-dev": [],
     "platform-overrides": {
-        "php": "7.3"
+        "php": "7.4"
     },
     "plugin-api-version": "2.1.0"
 }

lib/versioncheck.php

  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  *
  */
-// Show warning if a PHP version below 7.3 is used,
-if (PHP_VERSION_ID < 70300) {
+// Show warning if a PHP version below 7.4 is used,
+if (PHP_VERSION_ID < 70400) {
 	http_response_code(500);
-	echo 'This version of Nextcloud requires at least PHP 7.3<br/>';
+	echo 'This version of Nextcloud requires at least PHP 7.4<br/>';
 	echo 'You are currently running ' . PHP_VERSION . '. Please update your PHP version.';
 	exit(1);
 }

vendor-bin/cs-fixer/composer.json

 {
 	"config": {
 		"platform": {
-			"php": "7.3"
+			"php": "7.4"
 		}
 	},
 	"require": {

vendor-bin/cs-fixer/composer.lock

     "platform": [],
     "platform-dev": [],
     "platform-overrides": {
-        "php": "7.3"
+        "php": "7.4"
     },
     "plugin-api-version": "2.2.0"
 }

vendor-bin/psalm/composer.json

     },
     "config": {
         "platform": {
-            "php": "7.3"
+            "php": "7.4"
         },
         "allow-plugins": {
             "composer/package-versions-deprecated": true

vendor-bin/psalm/composer.lock

     "platform": [],
     "platform-dev": [],
     "platform-overrides": {
-        "php": "7.3"
+        "php": "7.4"
     },
     "plugin-api-version": "2.2.0"
 }