(MAGE2-323)[change] Adjust composer constraints.

composer.json

@@ -2,15 +2,15 @@
   "name": "heidelpay/magento2",
   "description": "This extension for Magento 2 provides a direct integration of the Heidelpay payment methods to your Magento 2 shop.",
   "require": {
-    "php": "~7.1.0 |~7.2.0|~7.3.0|~7.4.0",
-    "magento/module-config": "^102.0.0 | ^103.0.0",
-    "magento/module-store": "^102.0.0 | ^103.0.0",
-    "magento/module-checkout": "^102.0.0 | ^103.0.0",
+    "php": "~7.1.0 |~7.2.0 | ~7.3.0 | ~7.4.0",
+    "magento/module-config": "^101.0.0",
+    "magento/module-store": "^101.0.0",
+    "magento/module-checkout": "^100.0.0",
     "magento/module-sales": "^102.0.0 | ^103.0.0",
-    "magento/module-quote": "^102.0.0 | ^103.0.0",
+    "magento/module-quote": "^101.0.0",
     "magento/module-customer": "^102.0.0 | ^103.0.0",
-    "magento/module-payment": "^102.0.0 | ^103.0.0",
-    "magento/module-backend": "^102.0.0 | ^103.0.0",
+    "magento/module-payment": "^100.0.0",
+    "magento/module-backend": "^101.0.0 | ^102.0.0",
     "magento/framework": "^102.0.0 | ^103.0.0",
     "heidelpay/php-message-code-mapper": "~1.0",
     "heidelpay/php-basket-api": "~1.0",
@@ -25,7 +25,7 @@
     "allure-framework/allure-phpunit": "~1.2.0"
   },
   "suggest": {
-    "magento/module-checkout-agreements": "^102.0.0 | ^103.0.0"
+    "magento/module-checkout-agreements": "^100.0.0"
   },
   "repositories": [
     {