Update Composer & CI Workflow (#13)

Ideal flow is that composer can find the right versions of packages to fit the current version of PHP.

Author: aawnu

.github/workflows/ci.yml

@@ -28,15 +28,6 @@ jobs:
           ini-values: post_max_size=256M, max_execution_time=180
           coverage: xdebug
           tools: phpunit:${{ matrix.phpunit-versions }}
-      - if: ${{ matrix.php-versions == 7.0 }}
-        name: "PHP 7.0"
-        run: composer require --dev --with-all-dependencies --no-install phpunit/phpunit 6.0
-      - if: ${{ matrix.php-versions == 7.4 }}
-        name: "PHP 7.4"
-        run: composer require --dev --with-all-dependencies --no-install phpunit/phpunit 8.0
-      - if: ${{ matrix.php-versions >= 8.0 }}
-        name: "PHP >8.0"
-        run: composer require --dev --with-all-dependencies --no-install phpunit/phpunit
       - name: "Install"
         run: |
           composer update --no-install --with-all-dependencies

composer.json

@@ -9,10 +9,10 @@
         }
     },
     "require": {
-        "php": "^7.0 || ^8.0",
-        "guzzlehttp/guzzle": "^6.0 || ^7.0"
+        "php": "^7.0|^8.0",
+        "guzzlehttp/guzzle": "^6.0|^7.0"
     },
     "require-dev": {
-        "phpunit/phpunit": "^7.0 || ^8.0 || ^9.0"
+        "phpunit/phpunit": "^6.0|^7.0|^8.0|^9.0"
     }
 }