Issue #3417669 by quietone, longwave, smustgrave: Correct migrate related words

core/lib/Drupal/Core/Menu/MenuTreeStorage.php

core/misc/cspell/dictionary.txt

...s/block/src/Plugin/migrate/source/d7/BlockTranslation.php

.../Kernel/Plugin/migrate/source/d7/BlockTranslationTest.php

...rc/Kernel/Plugin/migrate/source/d6/BoxTranslationTest.php

...l/Plugin/migrate/source/d7/BlockCustomTranslationTest.php

core/modules/book/migrations/d6_book.yml

core/modules/book/migrations/d7_book.yml

core/modules/book/src/BookManager.php

core/modules/book/src/Plugin/migrate/source/Book.php

.../book/tests/src/Kernel/Plugin/migrate/source/BookTest.php

...ation/migrations/d6_field_instance_option_translation.yml

...ig_translation/migrations/d6_field_option_translation.yml

...ation/migrations/d6_language_content_comment_settings.yml

...ontent_translation/migrations/d6_menu_links_localized.yml

...tent_translation/migrations/d6_menu_links_translation.yml

...ontent_translation/migrations/d7_menu_links_localized.yml

...tent_translation/migrations/d7_menu_links_translation.yml

...nt_translation/migrations/node_translation_menu_links.yml

...lation/migrations/statistics_node_translation_counter.yml