Invalid config structures can result in exceptions when saving a config entity

I had multiple 8.4 upgrades failing with an error like this so far:

#0  Drupal\Core\Config\Schema\ArrayElement->get() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:179]
#1  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#2  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#3  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#4  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#5  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#6  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/StorableConfigBase.php:211]
#7  Drupal\Core\Config\StorableConfigBase->castValue() called at [/core/lib/Drupal/Core/Config/Config.php:212]
#8  Drupal\Core\Config\Config->save() called at [/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php:280]
#9  Drupal\Core\Config\Entity\ConfigEntityStorage->doSave() called at [/core/lib/Drupal/Core/Entity/EntityStorageBase.php:392]
#10 Drupal\Core\Entity\EntityStorageBase->save() called at [/core/lib/Drupal/Core/Config/Entity/ConfigEntityStorage.php:259]
#11 Drupal\Core\Config\Entity\ConfigEntityStorage->save() called at [/core/lib/Drupal/Core/Entity/Entity.php:377]
#12 Drupal\Core\Entity\Entity->save() called at [/core/lib/Drupal/Core/Config/Entity/ConfigEntityBase.php:637]
#13 Drupal\Core\Config\Entity\ConfigEntityBase->save() called at [/core/modules/views/views.post_update.php:213]
#14 {closure}()
#15 array_walk() called at [/core/modules/views/views.post_update.php:214]
#16 views_post_update_revision_metadata_fields() called at [/core/includes/update.inc:241]
#17 update_invoke_post_update() called at [/vendor/drush/drush/commands/core/drupal/batch.inc:163]
#18 _drush_batch_worker() called at [/vendor/drush/drush/commands/core/drupal/batch.inc:111]
#19 _drush_batch_command() called at [/vendor/drush/drush/includes/batch.inc:98]
#20 drush_batch_command() called at [/vendor/drush/drush/commands/core/drupal/update.inc:193]

So far, it was always a property inside a views filter, where it expects value to be a string but it's an array.

While it's bad that those mismatches exists, we ignore missing schema outside of tests, so I think we should also ignore those kind of problems, possibly just log them, without failing the update.

Example errors:
InvalidArgumentException: The configuration property display.default.display_options.filters.type.value.audio doesn't exist. in Drupal\Core\Config\Schema\ArrayElement->get() (line 76 of /h
InvalidArgumentException: The configuration property display.default.display_options.filters.type_1.value.image doesn't exist.