Restructure Umami's default content files so more than one language can be included

As initial patch, moved all the english content from
/default_content/article_body/ to /default_content/languages/en/article_body
/default_content/recipe_instructions/ to /default_content/languages/en/recipe_instructions

After moving that, installed it in my local, looks ok,

Just fixed the test and enabled the Spanish language

Sorry forgot to add the interdiff. :)

Removed the language configuration, applying the only the test fix,

Added parent issue.

I tested it and saw that all content is imported as it should from the new location /languages/en/.

I tested Umami's content again.
I installed Umami in English and went through every piece of content and each taxonomy.
Later I installed Umami in Hebrew, to make sure that another language doesn't cause any new issues.

For the end user - everything looks the same as it was before the patch.
The file structure has all the content files under /languages/en/

I fixed patch #17 by manually applying the changes in InstallHelper.php

patch #17 was created for 8.6.x
regular git apply -v 3028627_17.patch would fail with the message

Checking patch core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php...
error: while searching for:
  protected $state;

  /**
   * Constructs a new InstallHelper object.
   *
   * @param \Drupal\Core\Path\AliasManagerInterface $aliasManager

error: patch failed: core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php:47
error: core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php: patch does not apply

I found here https://www.drupal.org/patch/reroll#comment-8964453 about --3way option in git.
so running git apply -3 3028627_17.patch
resulted in

error: patch failed: core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php:47
Falling back to three-way merge...
Applied patch to 'core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php' with conflicts.
U core/profiles/demo_umami/modules/demo_umami_content/src/InstallHelper.php

Now all the files were staged, except for the merging conflict.
using GitKraken (which is awesome!) I could see clearly how to merge between the conflict of changes in the file since 8.6.x, and changes that are coming from the patch itself.

I found out that I missed 1 line of space, so I submitted this new patch.
I will RTBC it because there were no changes made since patch #17, just resolving a merge conflict.

Looks great, except:

+++ b/core/profiles/demo_umami/modules/demo_umami_content/default_content/languages/en/recipe_categories.csv
+Accompaniment
+Dessert
[...]
+++ b/core/profiles/demo_umami/modules/demo_umami_content/default_content/languages/en/tags.csv
+Alcohol free
+Baked
[...]

I find it strange that we hardwire numbers into the other CSV files referring to these terms, but then autogenerate those numbers programatically elsewhere. It would be more consistent if we would include the numbers in the terms files as well, and just use them in the code too.

This feels fragile even if I cannot exactly cite a situation where it would badly break, it feels like better to include the ID we use to refer to it rather than inferring it given that the files are hand-edited.

Updated to add IDs to the terms, so it's not reliant on row numbers matching up.

This latest patch installs without errors. Taxonomy terms are present as expected. Each term returns the tagged content on the term pages. The articles and recipes continue appear as expected.

Patch #30 works great.

I tested it as is,
then I created multiple modifications:

• Changed tags' ID
• Changed order of tags in the file while keeping original ID
• Created new ID that is not referenced in any recipe
• Added to recipes an ID that does not exist

It was working as intended and didn't produce any errors. On Umami itself - all taxonomy links behaved as expected, and nothing was linked to 404 pages.

Yay thanks! Committed. Let's get the translations (and their loading and exposure) happen next!