coding standards: require using strict type hinting almost everywhere

- the rules enforced (and will be automatically fixed) by slevomat PropertyTypeHintSniff, ReturnTypeHintSniff, and ParameterTypeHintSniff
- strict types are required in the whole codebase except entities, entity data objects, and a few particular classes that entities implement or extend
- removed redundatnt (and misconfigured) PhpdocToPropertyTypeFixer from the config

Author: vitek-rostislav

ecs.php

@@ -358,14 +358,9 @@
         // rule breaks jms/translation-bundle as it fails on this usage: `[, $b] = $var`
         // won't do any changes after upgrade
         ListSyntaxFixer::class => null,
-        // Enable MissingAnyTypeHint only
-        ParameterTypeHintSniff::class . '.' . ParameterTypeHintSniff::CODE_MISSING_NATIVE_TYPE_HINT,
         ParameterTypeHintSniff::class . '.' . ParameterTypeHintSniff::CODE_MISSING_TRAVERSABLE_TYPE_HINT_SPECIFICATION,
-        ParameterTypeHintSniff::class . '.' . ParameterTypeHintSniff::CODE_USELESS_ANNOTATION,
         ParameterTypeHintSniff::class . '.' . ParameterTypeHintSniff::CODE_USELESS_SUPPRESS,
-        ReturnTypeHintSniff::class . '.' . ReturnTypeHintSniff::CODE_MISSING_NATIVE_TYPE_HINT,
         ReturnTypeHintSniff::class . '.' . ReturnTypeHintSniff::CODE_MISSING_TRAVERSABLE_TYPE_HINT_SPECIFICATION,
-        ReturnTypeHintSniff::class . '.' . ReturnTypeHintSniff::CODE_USELESS_ANNOTATION,
         ReturnTypeHintSniff::class . '.' . ReturnTypeHintSniff::CODE_USELESS_SUPPRESS,
         ReturnTypeHintSniff::class . '.' . ReturnTypeHintSniff::CODE_LESS_SPECIFIC_NATIVE_TYPE_HINT,
     ]);