Make the theme compatible with Drupal 10

Providing patch for reference.
theme-compatibility

 core: 8.x
-core_version_requirement: ^8 || ^9
+core_version_requirement: ^8 || ^9 || ^10

core cannot be used with that value of core_version_requirement.

Here is a patch to get it working on drupal 10.

As mentioned by @apaderno, since, core can note be used have removed it. and added it like core_version_requirement: ^8.8 || ^9 || ^10.

prior to 8.7 core_version_requiremnt is not there.
maybe this link will be helpful https://www.drupal.org/node/3070687 →

Also, for File::load($fid[0] it was getting null value hence have added condition to check for Null.

@ashishsingh27 I have tested this theme on our local drupal 10 setup and it's working fine. now we will port these theme in drupal 10.
Thanks.

@ashishsingh27 I've created a new patch for it. It is working fine now. Please apply this patch and test it in your local drupal D10 setup.

Since there are not clear instructions a novice user can follow, this is not a novice issue.

 core: 8.x
-core_version_requirement: ^8 || ^9
+core_version_requirement: ^8 || ^9 || ^10

With that core_version_requirement value, core cannot be anymore used. Also, core_version_requirement should be core_version_requirement: ^8.8 || ^9 || ^10 because core_version_requirement is not recognized in earlier Drupal versions.

Has anybody verified the code is really compatible with Drupal 10? Is the code still using functions/methods that have been removed from Drupal 10?

I have reviewed the changes and tested them. I will merge them.