Issue #3126017: Add core version requirement support for drupal 9

composer.json

+{
+  "name": "drupal/easy_social",
+  "description": "Easily add share buttons to your nodes",
+  "type": "drupal-module",
+  "license": "GPL-2.0-or-later",
+  "minimum-stability": "dev",
+  "homepage": "https://www.drupal.org/project/easy_social",
+  "support": {
+    "issues": "https://www.drupal.org/project/issues/easy_social",
+    "source": "https://git.drupalcode.org/project/easy_social"
+  },
+  "require": {
+    "drupal/core": "^8 || ^9"
+  }
+}