[TASK] Provide the source code language in the code snippets in the R…

…EADME

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.github/CONTRIBUTING.md

@@ -84,12 +84,16 @@ schema once. Assuming that your database is named `phplist_test`, the user is
 named `phplist`, and the password is `batterystaple`, the command looks like
 this:
 
-    mysql -u phplist_test --password=batterystaple phplist_test < vendor/phplist/phplist4-core/Database/Schema.sql
+```bash
+mysql -u phplist_test --password=batterystaple phplist_test < vendor/phplist/phplist4-core/Database/Schema.sql
+```
 
 When running the integration tests, you will need to specify the database name
 and access credentials on the command line (in the same line):
 
-    PHPLIST_DATABASE_NAME=phplist_test PHPLIST_DATABASE_USER=phplist PHPLIST_DATABASE_PASSWORD=batterystaple vendor/bin/phpunit -c Configuration/PHPUnit/phpunit.xml Tests/Integration/
+```bash
+PHPLIST_DATABASE_NAME=phplist_test PHPLIST_DATABASE_USER=phplist PHPLIST_DATABASE_PASSWORD=batterystaple vendor/bin/phpunit -c Configuration/PHPUnit/phpunit.xml Tests/Integration/
+```
 
 
 ## Coding Style
@@ -103,18 +107,26 @@ We will only merge pull requests that follow the project's coding style.
 
 Please check your code with the provided PHP_CodeSniffer standard:
 
-    vendor/bin/phpcs --standard=vendor/phplist/phplist4-core/Configuration/PhpCodeSniffer/ Classes/ Tests/
+```bash
+vendor/bin/phpcs --standard=vendor/phplist/phplist4-core/Configuration/PhpCodeSniffer/ Classes/ Tests/
+```
 
 Please also check the code structure using PHPMD:
 
-    vendor/bin/phpmd Classes/ text vendor/phplist/phplist4-core/Configuration/PHPMD/rules.xml
+```bash
+vendor/bin/phpmd Classes/ text vendor/phplist/phplist4-core/Configuration/PHPMD/rules.xml
+```
 
 And also please run the static code analysis:
 
-    vendor/bin/phpstan analyse -l 5 Classes/ Tests/
+```bash
+vendor/bin/phpstan analyse -l 5 Classes/ Tests/
+```
 
 You can also run all code style checks using one long line from a bash shell:
-    find Classes/ Tests/ -name '*.php' -print0 | xargs -0 -n 1 -P 4 php -l && vendor/bin/phpstan analyse -l 5 Classes/ Tests/ && vendor/bin/phpmd Classes/ text vendor/phplist/phplist4-core/Configuration/PHPMD/rules.xml && vendor/bin/phpcs --standard=vendor/phplist/phplist4-core/Configuration/PhpCodeSniffer/ Classes/ Tests/
+```bash
+find Classes/ Tests/ -name '*.php' -print0 | xargs -0 -n 1 -P 4 php -l && vendor/bin/phpstan analyse -l 5 Classes/ Tests/ && vendor/bin/phpmd Classes/ text vendor/phplist/phplist4-core/Configuration/PHPMD/rules.xml && vendor/bin/phpcs --standard=vendor/phplist/phplist4-core/Configuration/PhpCodeSniffer/ Classes/ Tests/
+```
 
 This will execute all tests except for the unit tests and the integration
 tests.

README.md

@@ -124,7 +124,9 @@ increase web server performance:
 For running the application in development mode using the built-in PHP server,
 use this command:
 
-    bin/console server:run -d web/
+```bash
+bin/console server:run -d web/
+```
 
 The server will then listen on `http://127.0.0.1:8000` (or, if port 8000 is
 already in use, on the next free port after 8000).
@@ -136,14 +138,18 @@ You can stop the server with CTRL + C.
 To run the server in testing mode (which normally will only be needed for the
 automated tests, provide the `--env` option:
 
-    bin/console server:run -d web/ --env=test
+```bash
+bin/console server:run -d web/ --env=test
+```
 
 
 ## Useful Composer scripts
 
 You can get a list of all installed phpList modules with this command:
 
-    composer run-script list-modules
+```bash
+composer run-script list-modules
+```
 
 
 ## Creating a .tar.gz package of this distribution