feature #11274 initial setup for liniting the Documentation (OskarStark)

This PR was merged into the 3.4 branch.

Discussion
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initial setup for liniting the Documentation

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Commits
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f671fce initial DOCtor-RST setup.

Author: OskarStark

.doctor-rst.yaml

@@ -0,0 +1,73 @@
+rules:
+    no_inheritdoc: ~
+    avoid_repetetive_words: ~
+    blank_line_after_directive: ~
+    short_array_syntax: ~
+    no_app_console: ~
+    typo: ~
+    replacement: ~
+    composer_dev_option_not_at_the_end: ~
+    yarn_dev_option_at_the_end: ~
+    versionadded_directive_should_have_version: ~
+    deprecated_directive_should_have_version: ~
+    no_composer_req: ~
+    no_php_open_tag_in_code_block_php_directive: ~
+    no_blank_line_after_filepath_in_php_code_block: ~
+    no_blank_line_after_filepath_in_yaml_code_block: ~
+    no_blank_line_after_filepath_in_xml_code_block: ~
+    no_blank_line_after_filepath_in_twig_code_block: ~
+    php_prefix_before_bin_console: ~
+    use_deprecated_directive_instead_of_versionadded: ~
+    no_space_before_self_xml_closing_tag: ~
+    no_explicit_use_of_code_block_php: ~
+    ensure_order_of_code_blocks_in_configuration_block: ~
+    american_english: ~
+    valid_use_statements: ~
+    lowercase_as_in_use_statements: ~
+    ordered_use_statements: ~
+    no_namespace_after_use_statements: ~
+    correct_code_block_directive_based_on_the_content: ~
+    max_blank_lines:
+        max: 2
+    replace_code_block_types: ~
+    use_https_xsd_urls: ~
+    blank_line_before_directive: ~
+    extension_xlf_instead_of_xliff: ~
+    valid_inline_highlighted_namespaces: ~
+    indention: ~
+    unused_links: ~
+
+    #   3.4
+    versionadded_directive_major_version:
+        major_version: 3
+
+    versionadded_directive_min_version:
+        min_version: '3.0'
+
+# do not report as violation
+whitelist:
+    regex:
+        - '/FOSUserBundle(.*)\.yml/'
+        - '/``.yml``/'
+        - '/(.*)\.orm\.yml/' # currently DoctrineBundle only supports .yml
+    lines:
+        - 'in config files, so the old ``app/config/config_dev.yml`` goes to'
+        - '#. The most important config file is ``app/config/services.yml``, which now is'
+        - 'code in production without a proxy, it becomes trivially easy to abuse your'
+        - '.. _`EasyDeployBundle`: https://github.com/EasyCorp/easy-deploy-bundle'
+        - 'The bin/console Command'
+        - '# username is your full Gmail or Google Apps email address'
+        - '.. _`LDAP injection`: http://projects.webappsec.org/w/page/13246947/LDAP%20Injection'
+        - '.. versionadded:: 0.21.0' # Encore
+        - '.. versionadded:: 2.4.0' # SwiftMailer
+        - '.. versionadded:: 1.26' # Twig
+        - '.. versionadded:: 1.30' # Twig
+        - '.. versionadded:: 1.2' # MakerBundle
+        - '.. versionadded:: 1.11' # MakerBundle
+        - '.. versionadded:: 1.3' # MakerBundle
+        - '.. versionadded:: 1.8' # MakerBundle
+        - '0 => 123' # assertion for var_dumper - components/var_dumper.rst
+        - '1 => "foo"' # assertion for var_dumper - components/var_dumper.rst
+        - '$var .= "Because of this `\xE9` octet (\\xE9),\n";'
+        - "`Deploying Symfony 4 Apps on Heroku`_."
+        - ".. _`Deploying Symfony 4 Apps on Heroku`: https://devcenter.heroku.com/articles/deploying-symfony4"

.github/workflows/lint.yaml

@@ -0,0 +1,12 @@
+on: push
+name: Lint
+jobs:
+    doctor-rst:
+        name: DOCtor-RST
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@master
+            - name: DOCtor-RST
+              uses: docker://oskarstark/doctor-rst
+              with:
+                  args: --short