Coding standards errors

There are some coding standards issues that will be great to fix. @shumer, if you don't mind we will do it on Lutsk code sprint :)

Here is the summary:

PHP CODE SNIFFER REPORT SUMMARY
----------------------------------------------------------------------
FILE                                                  ERRORS  WARNINGS
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.../modules/contrib/config_pages/config_pages.module  12      4
...modules/contrib/config_pages/config_pages.install  4       1
...ntrib/config_pages/src/Entity/ConfigPagesType.php  9       2
...ntrib/config_pages/src/ConfigPagesListBuilder.php  3       1
...ges/src/Form/ConfigPagesClearConfirmationForm.php  1       2
...nfig_pages/src/Form/ConfigPagesTypeDeleteForm.php  0       2
...b/config_pages/src/ConfigPagesTypeListBuilder.php  0       1
...ntrib/config_pages/src/ConfigPagesContextBase.php  4       0
...contrib/config_pages/src/ConfigPagesInterface.php  1       6
...contrib/config_pages/src/ConfigPagesViewsData.php  1       0
.../config_pages/src/ConfigPagesContextInterface.php  3       0
...ib/config_pages/src/Routing/ConfigPagesRoutes.php  2       0
...ules/contrib/config_pages/src/ConfigPagesForm.php  0       3
...onfig_pages/src/Annotation/ConfigPagesContext.php  1       0
...ib/config_pages/src/ConfigPagesContextManager.php  4       0
..._pages/src/ConfigPagesContextManagerInterface.php  1       0
...ig_pages/src/Controller/ConfigPagesController.php  4       2
.../contrib/config_pages/src/ConfigPagesTypeForm.php  9       4
...onfig_pages/src/Plugin/Block/ConfigPagesBlock.php  1       4
..._pages/src/Plugin/ConfigPagesContext/Language.php  5       0
...ebase/web/modules/contrib/config_pages/README.txt  0       24
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A TOTAL OF 65 ERRORS AND 56 WARNINGS WERE FOUND IN 21 FILES
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