Bump PHP support from 8.1 to 8.5

We want to release version 3.0 as fresh as possible, without having to
maintain backward compatibility with the previous versions. Because that
version will be on for some time, we decided it will be best to support
only PHP version 8.5 or higher.

Acked-by: Alexandre Gomes Gaigalas <alganet@gmail.com>

.github/workflows/continuous-integration.yml

@@ -19,10 +19,7 @@ jobs:
     strategy:
       matrix:
         php-version:
-          - "8.1"
-          - "8.2"
-          - "8.3"
-          - "8.4"
+          - "8.5"
 
     steps:
       - name: Checkout
@@ -61,7 +58,7 @@ jobs:
       - name: Install PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: 8.1
+          php-version: 8.5
           coverage: pcov
 
       - name: Install Localisation Files
@@ -93,7 +90,7 @@ jobs:
       - name: Install PHP
         uses: shivammathur/setup-php@v2
         with:
-          php-version: 8.4
+          php-version: 8.5
           coverage: none
 
       - name: Install dependencies